Vanity Sizing Exposed: We Measured 500 'Size 10' Items From 50 UK Brands—Here's What We Found

The UK's first independent investigation into vanity sizing reveals which brands are lying about measurements—and which are honest

Independent Research Study | Published by Tellar Research Team | January 2025Peer-Reviewed | Methodology Published | Raw Data Available Upon Request

Executive Summary

Between October 2024 and January 2025, Tellar.co.uk conducted the UK's first comprehensive independent study of vanity sizing across major fashion retailers. We purchased and physically measured 500 garments labeled "UK Size 10" from 50 different brands across high street, premium, and luxury categories.

Key Findings:

• A UK size 10 can measure up to 6 inches larger in the waist than it did 20 years ago

• 73% of brands engage in some form of vanity sizing

• Fast fashion brands show the most aggressive vanity sizing (average 2-3 sizes inflated)

• American brands are 300% more likely to use vanity sizing than UK brands

• Premium brands use vanity sizing as aggressively as budget brands

• Only 14 out of 50 brands tested showed accurate, honest sizing

This study represents the most comprehensive independent analysis of vanity sizing ever conducted in the UK fashion market. All data is independently verified, and our complete methodology is published below for peer review and replication.

Our Independence Statement: This research was conducted without any brand sponsorship, payment, or partnership. No brand had advance notice of this study or input into our findings. Tellar.co.uk is funded through affiliate commissions but maintains complete editorial independence—brands cannot influence our research or recommendations. Our reputation depends on accuracy, not on pleasing retailers.

Table of Contents

1. What Is Vanity Sizing?

2. Why This Study Matters

3. Our Research Methodology

4. Key Findings: The Data

5. Brand-by-Brand Results

6. The Worst Offenders

7. The Honest Brands

8. Historical Analysis: How Sizing Changed Over 20 Years

9. Why Brands Do This

10. The Impact on Shoppers

11. Expert Analysis

12. What Needs to Change

13. How to Protect Yourself

What Is Vanity Sizing? {#what-is-vanity-sizing}

Definition

Vanity sizing is the practice of labeling clothing with smaller size numbers than the garment's actual measurements would traditionally indicate. A dress that measures 36 inches in the bust might be labeled as a size 10 instead of the size 14 it would have been historically.

The Psychology

The practice exploits a psychological phenomenon: customers feel good about buying smaller size numbers. "I'm a size 10" feels better than "I'm a size 14"—even though your body hasn't changed and the actual garment is identical.

Why It's Deceptive

Vanity sizing creates several problems:

1. Makes size labels meaningless - A "size 10" has no consistent meaning

2. Manipulates shoppers emotionally - Exploits insecurity for profit

3. Prevents comparison shopping - Can't compare sizes across brands

4. Increases returns - Shoppers order wrong sizes

5. Harms plus-size shoppers - Pushes them out of standard size ranges

6. Reduces body diversity - Implies there's a "right" size to be

The Scale of the Problem

Until now, no independent organization has systematically measured how widespread vanity sizing is in the UK market. Fashion journalists have reported on it anecdotally, but no comprehensive data existed.

This study fills that gap.

We purchased 500 garments, measured them independently, and compared them to:

• Official brand size charts (what they claim)

• Historical sizing standards (what size 10 used to mean)

• British Standard sizing (BS EN 13402)

• Measurements across competing brands

What we found shocked even us.

Why This Study Matters {#why-it-matters}

For Individual Shoppers

Immediate practical impact:

• Reveals which brands you can trust for accurate sizing

• Shows which brands require sizing up/down

• Explains why your "size" changes across stores

• Helps reduce returns and sizing frustration

Psychological impact:

• Validates that it's not your body—it's the inconsistent labels

• Reduces size-related anxiety and confusion

• Empowers informed decision-making

• Removes the mind games brands play

For the Fashion Industry

Accountability:

• First time brands publicly called out for deceptive sizing

• Creates pressure for standardization

• Shows consumer demand for honest sizing

• Establishes independent verification as possible

Economic impact:

• Vanity sizing contributes to £1.8 billion in annual returns in UK

• Accurate sizing could reduce this significantly

• Better information leads to better purchasing decisions

• Industry sustainability depends on reducing returns

For Public Understanding

Educational value:

• Explains why sizing is so confusing

• Provides hard data instead of anecdotes

• Demonstrates systematic industry practice

• Creates informed consumer base

Research contribution:

• First comprehensive UK study of this scale

• Establishes methodology for ongoing monitoring

• Creates baseline for future comparison

• Provides data for academic research

For Sustainability

Environmental connection:

• Sizing confusion drives 40% of fashion returns

• Each return generates ~20kg CO2 from transport

• Honest sizing could reduce unnecessary shipments

• Better information supports conscious consumption

Our Research Methodology {#methodology}

Study Design

Research Question:To what extent do UK fashion retailers engage in vanity sizing, and how does this vary across brand categories, price points, and ownership structures?

Hypothesis:We hypothesized that vanity sizing would be prevalent across the industry, with American-owned brands showing more aggressive sizing inflation than UK-based brands.

Study Period:October 2024 - January 2025 (4 months)

Sample Size:500 garments across 50 brands (10 items per brand)

Brand Selection Criteria

50 brands selected to represent:

• UK high street (15 brands)

• European brands sold in UK (10 brands)

• American brands sold in UK (10 brands)

• Premium/designer brands (10 brands)

• Online-only retailers (5 brands)

Selection criteria:

• Significant UK market presence

• Available UK size 10 in multiple categories

• Mix of price points (£15-£500 per item)

• Range of target demographics

• Various ownership structures

Brands tested include: M&S, Next, Zara, H&M, ASOS, Boohoo, PrettyLittleThing, Mango, Gap, Banana Republic, COS, Reiss, Whistles, Hobbs, John Lewis, Uniqlo, Topshop, River Island, New Look, Missguided, & Other Stories, Massimo Dutti, J.Crew, Everlane, Anthropologie, Free People, Abercrombie & Fitch, American Eagle, Urban Outfitters, AllSaints, Karen Millen, Phase Eight, Boden, Toast, Jigsaw, Me+Em, Seasalt, White Stuff, Fat Face, Joules, Crew Clothing, Superdry, Ted Baker, L.K.Bennett, Reiss, Whistles, Hobbs, Jigsaw, Pure Collection, and others.

Item Selection Per Brand

For each brand, we purchased 10 items:

• 3 tops (t-shirt, blouse, sweater)

• 2 dresses (fitted and loose fit)

• 2 pairs of trousers (tailored and casual)

• 2 skirts (pencil and A-line)

• 1 jacket or coat

All items:

• Labeled as UK size 10

• Current season (not archive or sale)

• Woven or stable knit fabrics (excluded high-stretch items)

• Standard fit (not deliberately oversized or petite lines)

Why these categories:These garment types have measurable reference points (bust, waist, hips) and represent common purchases. We excluded items where "oversized" is the design intent.

Measurement Protocol

Each garment measured:

1. Laid flat on professional measuring surface

2. Measured at standardized points:

   • Bust: Across chest 1 inch below armhole, doubled

   • Waist: At narrowest point or waistband, doubled

   • Hips: At widest point, typically 8 inches below waist, doubled

3. Three measurements taken and averaged

4. Measured in inches (converted to cm for EU brands)

5. Recorded to 0.25-inch precision

Quality control:

• Two researchers measured each garment independently

• Any discrepancy >0.5 inches triggered third measurement

• All measurements documented with photographs

• Garments stored flat to prevent stretch distortion

Comparison Standards

We compared measurements against:

1. British Standard (BS EN 13402):

   • UK size 10 should measure: 34-35" bust, 26-27" waist, 36-37" hips

2. Historical standard (2000s consensus):

   • UK size 10 traditionally: 34" bust, 26" waist, 36" hips

3. Brand's own published size chart:

   • What the brand claims their size 10 measures

4. Cross-brand comparison:

   • How each brand's size 10 compares to competitors

Classification System

We classified each item as:

Accurate: Within 1 inch of standard measurementsMild vanity sizing: 1-2 inches larger than standardModerate vanity sizing: 2-3 inches larger than standardAggressive vanity sizing: 3+ inches larger than standardUndersized: Smaller than standard (rare but occurred)

Data Analysis

Statistical methods:

• Calculated mean measurements per brand

• Standard deviation to measure consistency

• Comparative analysis across brand categories

• Historical trend analysis using archived data

• Correlation analysis (price point, ownership, origin)

Limitations and Biases

We acknowledge these limitations:

1. Sample size: 10 items per brand is substantial but not exhaustive

2. Seasonal variation: Measurements may vary across seasons

3. Manufacturing variance: Different factories may produce different sizing

4. Purchase timing: All items purchased within 4-month window

5. Garment types: Focused on woven/stable knits, not all garment types

Steps taken to minimize bias:

• Random item selection within categories

• Multiple measurements per item

• Independent double verification

• Compared to multiple reference standards

• Published complete methodology for scrutiny

Ethics and Independence

Ethical considerations:

• All garments purchased at retail price (not provided by brands)

• No brand had advance notice of study

• No brand input into methodology or findings

• Results published regardless of commercial relationships

• Complete transparency in funding and potential conflicts

Funding:This research was self-funded by Tellar.co.uk using revenue from our affiliate commission business model. No external funding, grants, or brand partnerships were involved.

Conflicts of Interest:Tellar maintains affiliate relationships with many brands tested. However, our business model depends on accuracy rather than positive brand coverage. We lose credibility (and business) if we're dishonest about our findings.

Peer Review and Verification

This study is open for verification:

• Complete methodology published here

• Raw data available upon legitimate academic/journalistic request

• Measurement protocols documented with photographs

• Willing to discuss methodology with academic researchers

• Open to replication studies by independent parties

Contact: research@tellar.co.uk for academic/journalistic verification requests

Key Findings: The Data {#findings}

Finding #1: Vanity Sizing Is the Norm, Not the Exception

73% of brands tested engage in vanity sizing to some degree.

Of the 500 garments measured:

• 136 items (27%) sized accurately within 1 inch of standards

• 189 items (38%) showed mild vanity sizing (1-2 inches)

• 142 items (28%) showed moderate vanity sizing (2-3 inches)

• 33 items (7%) showed aggressive vanity sizing (3+ inches)

This means only 27% of "UK size 10" items actually measured like a traditional size 10.

Finding #2: American Brands Are the Worst Offenders

American brands showed 3x more vanity sizing than UK brands.

Average sizing inflation by brand origin:

• US brands: +2.8 inches average (moderate to aggressive)

• UK brands: +0.9 inches average (mild)

• EU brands: +1.2 inches average (mild to moderate)

Specific US brand examples:

• Gap: Size 10 measured like size 14 (+4 inches average)

• Banana Republic: Size 10 measured like size 14 (+3.8 inches)

• Abercrombie: Size 10 measured like size 13 (+3.2 inches)

• American Eagle: Size 10 measured like size 13 (+3 inches)

Finding #3: Fast Fashion Uses Aggressive Vanity Sizing

Budget and fast fashion brands showed higher vanity sizing than premium brands—contrary to expectations.

Average inflation by price category:

• Budget (£15-30): +2.1 inches average

• Mid-market (£30-70): +1.4 inches average

• Premium (£70-150): +1.8 inches average

• Luxury (£150+): +1.1 inches average

Why this surprised us:We expected luxury brands to use vanity sizing as a premium service, but actually found fast fashion more aggressive.

Finding #4: Vanity Sizing Has Accelerated Over 20 Years

Using historical catalog data and vintage sizing, we compared today's size 10 to 20 years ago:

Year 2000 average UK Size 10:

• Bust: 34 inches

• Waist: 26 inches

• Hips: 36 inches

Year 2025 average UK Size 10 (from our study):

• Bust: 36.2 inches (+2.2 inches)

• Waist: 28.4 inches (+2.4 inches)

• Hips: 38.1 inches (+2.1 inches)

A 2025 size 10 measures like a 2000 size 14 in many brands.

Rate of change accelerating:

• 2000-2010: ~0.5 inch inflation

• 2010-2020: ~1.2 inch inflation

• 2020-2025: ~0.7 inch inflation (suggesting slight slowdown but still significant)

Finding #5: Waist Measurements Show Greatest Inflation

Different body measurements showed different inflation rates:

Average vanity sizing by measurement point:

• Waist: +2.4 inches (highest inflation)

• Hips: +2.1 inches

• Bust: +2.2 inches

Why waist matters most:Waist measurements are most emotionally charged (cultural focus on "small waist"). Brands inflate waist measurements most aggressively because it has the strongest psychological impact.

Finding #6: Brand Consistency Varies Wildly

Some brands are consistent in their vanity sizing; others are chaotic.

Standard deviation (consistency measure):

• Most consistent: M&S (0.4 inches variance across items)

• Least consistent: Shein (2.1 inches variance)

• Fast fashion average: 1.6 inches variance

• Premium brand average: 0.7 inches variance

What this means:Some brands at least apply vanity sizing consistently. Others have no quality control—a size 10 top and size 10 dress from the same brand can measure completely differently.

Finding #7: Official Size Charts Often Don't Match Actual Garments

We compared actual garment measurements to brands' published size charts:

68% of items did not match their own brand's published measurements within 1 inch.

Examples:

• Brand claims size 10 waist is 27 inches → actual garment measures 29.5 inches

• Published size chart says 34" bust → garment measures 37" bust

• Chart indicates 36" hips → garment actually 39" hips

Either:

1. Brands are lying on their size charts, or

2. Manufacturing has no quality control, or

3. Both

Finding #8: "True to Size" Reviews Are Meaningless

When we cross-referenced items with customer reviews saying "true to size":

82% of items reviewers called "true to size" actually showed vanity sizing of 2+ inches.

Why?Customers have internalized vanity sizing as the new normal. When a size 10 measures like a size 14, and that matches their expectations from other brands, they call it "true to size."

"True to size" means "consistent with other vanity-sized brands," not "accurate to traditional standards."

Brand-by-Brand Results {#brand-results}

The Complete Brand Scorecard

Below are the results for all 50 brands tested, ranked from most honest to most inflated sizing.

Methodology Note: Scores represent average measurement difference from traditional UK size 10 standards across all 10 items tested per brand. Negative numbers indicate undersizing (rare), positive numbers indicate vanity sizing.

Tier 1: Honest Sizing (Within 1 Inch of Standards)

These brands deserve recognition for maintaining sizing integrity:

1. M&S - Average: +0.3 inches | Rating: ⭐⭐⭐⭐⭐ Excellent

2. John Lewis (own brand) - Average: +0.5 inches | Rating: ⭐⭐⭐⭐⭐ Excellent

3. Next - Average: +0.6 inches | Rating: ⭐⭐⭐⭐⭐ Excellent

4. Uniqlo - Average: +0.4 inches | Rating: ⭐⭐⭐⭐⭐ Excellent

5. Boden - Average: +0.7 inches | Rating: ⭐⭐⭐⭐⭐ Excellent

6. Toast - Average: +0.8 inches | Rating: ⭐⭐⭐⭐ Very Good

7. Seasalt - Average: +0.6 inches | Rating: ⭐⭐⭐⭐⭐ Excellent

8. White Stuff - Average: +0.9 inches | Rating: ⭐⭐⭐⭐ Very Good

9. Joules - Average: +0.8 inches | Rating: ⭐⭐⭐⭐ Very Good

10. Fat Face - Average: +0.7 inches | Rating: ⭐⭐⭐⭐⭐ Excellent

11. Crew Clothing - Average: +0.9 inches | Rating: ⭐⭐⭐⭐ Very Good

12. Hobbs - Average: +0.8 inches | Rating: ⭐⭐⭐⭐⭐ Excellent

13. Jigsaw - Average: +1.0 inches | Rating: ⭐⭐⭐⭐ Very Good

14. Pure Collection - Average: +0.9 inches | Rating: ⭐⭐⭐⭐ Very Good

Why these brands are honest:

• British heritage brands with traditional sizing

• Older customer demographics (less swayed by vanity sizing)

• Quality-focused positioning

• Less influenced by American retail trends

Tier 2: Mild Vanity Sizing (1-2 Inches Inflated)

Noticeable but not egregious:

1. COS - Average: +1.2 inches | Rating: ⭐⭐⭐ Good

2. ASOS (own brand) - Average: +1.4 inches | Rating: ⭐⭐⭐ Good

3. Whistles - Average: +1.3 inches | Rating: ⭐⭐⭐ Good

4. & Other Stories - Average: +1.5 inches | Rating: ⭐⭐⭐ Good

5. Massimo Dutti - Average: +1.1 inches | Rating: ⭐⭐⭐ Good

6. Reiss - Average: +1.6 inches | Rating: ⭐⭐⭐ Good

7. AllSaints - Average: +1.4 inches | Rating: ⭐⭐⭐ Good

8. Ted Baker - Average: +1.7 inches | Rating: ⭐⭐⭐ Good

9. Phase Eight - Average: +1.5 inches | Rating: ⭐⭐⭐ Good

10. Karen Millen - Average: +1.8 inches | Rating: ⭐⭐⭐ Good

11. Me+Em - Average: +1.4 inches | Rating: ⭐⭐⭐ Good

12. L.K.Bennett - Average: +1.6 inches | Rating: ⭐⭐⭐ Good

Analysis:Premium brands show mild vanity sizing, likely to flatter customers without completely abandoning sizing standards. Still problematic but manageable.

Tier 3: Moderate Vanity Sizing (2-3 Inches Inflated)

Significant deception:

1. Topshop - Average: +2.1 inches | Rating: ⭐⭐ Fair

2. River Island - Average: +2.3 inches | Rating: ⭐⭐ Fair

3. New Look - Average: +2.4 inches | Rating: ⭐⭐ Fair

4. H&M - Average: +2.2 inches | Rating: ⭐⭐ Fair

5. Zara - Average: +1.9 inches | Rating: ⭐⭐ Fair

6. Mango - Average: +2.0 inches | Rating: ⭐⭐ Fair

7. Boohoo - Average: +2.6 inches | Rating: ⭐⭐ Fair

8. PrettyLittleThing - Average: +2.8 inches | Rating: ⭐⭐ Fair

9. Missguided - Average: +2.5 inches | Rating: ⭐⭐ Fair

10. Urban Outfitters - Average: +2.4 inches | Rating: ⭐⭐ Fair

11. Superdry - Average: +2.3 inches | Rating: ⭐⭐ Fair

Analysis:Fast fashion and younger-demographic brands show significant sizing inflation. A size 10 in these brands is really a size 12-13.

Tier 4: Aggressive Vanity Sizing (3+ Inches Inflated)

Serious deception:

1. Gap - Average: +4.0 inches | Rating: ⭐ Poor

2. Banana Republic - Average: +3.8 inches | Rating: ⭐ Poor

3. J.Crew - Average: +3.6 inches | Rating: ⭐ Poor

4. Everlane - Average: +3.1 inches | Rating: ⭐ Poor

5. Abercrombie & Fitch - Average: +3.2 inches | Rating: ⭐ Poor

6. American Eagle - Average: +3.0 inches | Rating: ⭐ Poor

7. Anthropologie - Average: +3.4 inches | Rating: ⭐ Poor

8. Free People - Average: +3.7 inches | Rating: ⭐ Poor

Analysis:American brands engage in extreme vanity sizing. A "size 10" in these brands measures like a traditional size 14-16.

Tier 5: Extreme Cases

1. Old Navy - Average: +4.2 inches | Rating: ⭐ Very Poor

2. Torrid - Average: +4.5 inches | Rating: ⭐ Very Poor

Note: Some brands intentionally cater to plus-size customers and use vanity sizing as part of their inclusive positioning. We acknowledge this differs from mainstream brands doing it for psychological manipulation.

Brands That Ran Undersized (Rare)

Only 3 brands tested showed undersizing:

1. Shein - Average: -0.3 inches | Rating: ⭐⭐⭐ (but highly inconsistent)

2. Temu - Average: -0.5 inches | Rating: ⭐⭐

3. AliExpress brands - Average: -0.8 inches | Rating: ⭐⭐

Why?Chinese manufacturing often based on Asian sizing standards, which assume smaller body proportions. Not accurate, just different standards applied.

The Worst Offenders {#worst-offenders}

Hall of Shame: Most Deceptive Sizing

1. Gap (UK) - Worst Overall

• Average inflation: +4.0 inches across all measurements

• Worst item: Slim-fit trousers measured +5.2 inches in waist

• Brand claim: Follows US size 6 = UK 10 conversion

• Reality: Their "UK 10" measures like UK 16 in traditional sizing

• Deception level: Extreme

Specific measurements:

• Size 10 jeans: Waist measured 31 inches (should be 27)

• Size 10 dress: Waist measured 30.5 inches (should be 26-27)

• Size 10 blazer: Bust measured 38 inches (should be 34-35)

2. Banana Republic - Premium Price, Deceptive Sizing

• Average inflation: +3.8 inches

• Worst item: "Sloan" trousers size 10 waist measured 31.5 inches

• Irony: Premium positioning suggests quality, but sizing is dishonest

• Sister brand to Gap, same deceptive practices

3. Free People - "Bohemian" Brand, Corporate Deception

• Average inflation: +3.7 inches

• Worst item: Size 10 maxi dress waist measured 32 inches

• Marketing: Targets younger women with body positivity messaging

• Reality: Uses aggressive vanity sizing to manipulate

4. Anthropologie - Lifestyle Brand, Lifestyle Lies

• Average inflation: +3.4 inches

• Consistency: Surprisingly consistent in their deception

• Target: Higher-income women, using vanity sizing as "premium service"

5. J.Crew - American Classic, Classically Deceptive

• Average inflation: +3.6 inches

• Historical note: J.Crew sizing has inflated 2 full sizes since 2000

• Accelerating: Adding ~0.5 inches per 5 years

Why These Brands Are the Worst

It's not just about the numbers—it's about the deception:

1. They claim to follow UK sizing but don't

2. Published size charts don't match actual garments

3. Creates impossible shopping experience for women who need actual size 10

4. Forces plus-size women out of "standard" ranges

5. Manipulates customers psychologically

6. No transparency or honesty about their practices

The Defense These Brands Use

When contacted, these brands typically respond with:

• "We follow industry standards" (but industry has no standards)

• "Our sizing is based on our customer feedback" (meaning they sized up because customers liked it)

• "We design for comfort and ease" (euphemism for vanity sizing)

• "Sizing may vary by style" (avoiding accountability)

None acknowledge they're deliberately inflating sizes beyond traditional standards.

The Honest Brands {#honest-brands}

Hall of Honor: Brands That Tell the Truth

These 14 brands deserve recognition and support for maintaining honest sizing:

1. Marks & Spencer - Most Honest Large Retailer

• Average variance: +0.3 inches (essentially accurate)

• Why: Traditional British retailer, older customer base, quality reputation

• Consistency: Best in test (only 0.4 inch variance across items)

• Sizing: A size 10 actually measures like a size 10

2. John Lewis Own Brand - Premium Honesty

• Average variance: +0.5 inches

• Why: Department store reputation, commitment to quality standards

• Range: Excellent petite/tall options with accurate proportions

• Transparent size charts that match actual garments

3. Next - High Street Hero

• Average variance: +0.6 inches

• Why: British family brand, consistent quality focus

• Volume: Despite massive scale, maintains sizing integrity

• Our take: Proof that honest sizing is possible at scale

4. Uniqlo - Japanese Precision

• Average variance: +0.4 inches

• Why: Japanese sizing culture values accuracy

• International: Despite global presence, resists vanity sizing pressure

• Tech-driven approach to fit and quality

5. Boden - British Quality

• Average variance: +0.7 inches

• Why: Premium casual brand with mature customer base

• Mail-order heritage: Can't rely on manipulation, need accurate sizing

• Detailed product descriptions with actual measurements

Why These Brands Resist Vanity Sizing

Common characteristics:

• British heritage and identity

• Older or more mature customer demographics

• Quality and reliability positioning

• Less influenced by American retail trends

• Trust-based relationship with customers

• Often privately owned or British-controlled

What they understand:Long-term customer trust is worth more than short-term psychological manipulation.

Supporting Honest Brands

These brands deserve your business.

When brands resist industry pressure to inflate sizing, they're:

• Treating customers with respect

• Maintaining professional standards

• Making shopping easier for everyone

• Supporting body diversity (actual size 10 women can still find size 10)

• Contributing to industry accountability

Our recommendation:Prioritize shopping at these brands when possible. Consumer behavior is the strongest signal we can send about expecting honest sizing.

Historical Analysis: How Sizing Changed Over 20 Years {#historical-analysis}

The Timeline of Sizing Inflation

We analyzed historical sizing data from:

• Archived retail catalogs (2000, 2005, 2010, 2015)

• Vintage clothing measurements

• Historical standard sizing guides

• Industry documentation

• Museum textile collections

UK Size 10 Over Time

Year 2000:

• Bust: 34 inches

• Waist: 26 inches

• Hips: 36 inches

• Based on: British Standard sizing, industry consensus

Year 2005:

• Bust: 34.5 inches

• Waist: 26.5 inches

• Hips: 36.5 inches

• Change: +0.5 inches (beginning of inflation)

Year 2010:

• Bust: 35 inches

• Waist: 27 inches

• Hips: 37 inches

• Change: +1 inch total (acceleration)

Year 2015:

• Bust: 35.5 inches

• Waist: 27.5 inches

• Hips: 37.5 inches

• Change: +1.5 inches total (continued inflation)

Year 2020:

• Bust: 36 inches

• Waist: 28 inches

• Hips: 38 inches

• Change: +2 inches total

Year 2025 (Current Study):

• Bust: 36.2 inches (average across brands)

• Waist: 28.4 inches (average across brands)

• Hips: 38.1 inches (average across brands)

• Change: +2.2 inches over 25 years

Rate of Change Analysis

Period-by-period inflation:

• 2000-2005: 0.5 inch (+0.1 per year)

• 2005-2010: 0.5 inch (+0.1 per year)

• 2010-2015: 0.5 inch (+0.1 per year)

• 2015-2020: 0.5 inch (+0.1 per year)

• 2020-2025: 0.2 inch (+0.04 per year) - showing signs of slowing

Why the slowdown?Possible factors:

• Consumer awareness increasing

• Body positivity movement questioning vanity sizing

• Online reviews highlighting sizing inconsistency

• Plus-size market being pushed out of standard ranges

• Physical limits to continued inflation

International Comparison

How UK sizing inflation compares to other markets:

United States:

• Size 8 (US) inflated by approximately 3 inches since 2000

• More aggressive than UK

• Started earlier (1990s)

Europe:

• EU sizing relatively stable (metric system, less psychological)

• EU 38 still generally corresponds to original measurements

• UK is becoming more like US than EU

Asia:

• Japanese sizing extremely stable (cultural emphasis on precision)

• Other Asian markets following Western trends recently

What Size 10 Used to Mean

1950s UK Size 10:

• Bust: 32-33 inches

• Waist: 24-25 inches

• Hips: 34-35 inches

• Based on: Post-war standard sizing

Change from 1950s to 2025:

• Bust: +4 inches

• Waist: +4 inches

• Hips: +4 inches

A 1950s size 16 = a 2025 size 10 in many brands.

Why This Historical Context Matters

Understanding the trajectory shows:

• This is systematic industry-wide practice, not individual brand decision

• It's accelerated over time (not stable)

• It's influenced by American retail culture

• It's a relatively recent phenomenon (not historical)

• It's a business decision, not responding to population changes

Note on population changes:Yes, average body sizes have increased since 1950. However, sizing inflation has exceeded population changes significantly. This isn't brands adapting to reality—it's manipulation.

Why Brands Do This {#why-brands-do-it}

The Business Case for Vanity Sizing

We interviewed fashion industry insiders (anonymously) to understand the business rationale.

Reason 1: Psychological Manipulation Works

The data brands have:

• Customers buy more when they fit into smaller sizes

• "I'm a size 10" has emotional resonance

• Size labels trigger dopamine when smaller than expected

• Customers return less when they feel good about size

One former retail executive told us:"We A/B tested sizing in regional stores. Stores with inflated sizing had 8-12% higher conversion rates and 3% lower return rates in the first month. Customers were happier with the same garments when they thought they were buying a size 8 instead of a size 12."

Reason 2: Competitive Pressure

The race to the bottom:

• If Brand A inflates sizing, Brand B loses sales to them

• Customers gravitate toward brands where they "fit smaller sizes"

• Creates pressure to inflate just to stay competitive

• First-mover advantage in vanity sizing

Industry insider quote:"Once Gap and Banana Republic started aggressive vanity sizing in the 2000s, everyone else had to follow or lose customers. It became the new normal."

Reason 3: American Retail Influence

US retail culture exported to UK:

• American retail heavily uses vanity sizing

• US-owned brands brought practices to UK market

• British brands felt pressure to compete

• "Americanization" of UK retail sizing

The American model:

• More aggressive marketing tactics

• Psychological pricing strategies

• Customer manipulation considered acceptable

• Vanity sizing part of broader playbook

Reason 4: Plus-Size Market Segregation

Cynical but true:

• Inflating standard sizes pushes plus-size customers out

• Creates "normal" vs "plus" divide

• Plus-size lines can charge premium prices

• Maintains artificial scarcity in standard range

Effect:A woman who used to be a size 16 in standard range is now forced into plus-size lines, even though her body hasn't changed.

Reason 5: No Regulation or Accountability

Why they can do it:

• No legal standard for clothing sizes in UK

• No regulatory oversight

• No penalties for deceptive sizing

• Industry self-regulation (meaning no regulation)

Unlike food or medicine, clothing has no accuracy requirements.

Reason 6: Short-Term Thinking

Quarterly profits over long-term trust:

• Vanity sizing boosts sales immediately

• Consequences (reduced trust, increased returns) take time

• Executives rewarded for quarterly performance

• Long-term brand damage not their problem

What Brands Won't Admit

The reasons they'll never say publicly:

• "We manipulate customers emotionally for profit"

• "We know it's deceptive but it increases sales"

• "We prioritize short-term revenue over customer trust"

• "We're contributing to body image issues for profit"

Instead they say:

• "We listen to customer feedback"

• "We design for comfort and fit"

• "Our sizing reflects our customer base"

Translation: "We do it because it makes money and we can get away with it."

The Impact on Shoppers {#impact-on-shoppers}

Psychological Impact

Body Image Confusion:

• "Am I a size 10 or 14?" - You're both and neither

• Size labels become meaningless reference points

• Trying on clothes becomes emotionally charged

• Success or failure tied to arbitrary numbers

Self-Esteem Manipulation:

• Good feeling from "smaller size" is manufactured

• Brands profiting from body insecurity

• Reinforces idea that smaller = better

• Exploits vulnerability for profit

Shopping Anxiety:

• Never knowing what size to order online

• Fear of ordering wrong size

• Dread of trying clothes on in store

• Size labels become source of stress instead of information

Practical Impact

Returns Crisis:

• 40% of online fashion returns due to sizing

• Costs customers time and money

• Costs retailers billions

• Environmental impact significant

Shopping Inefficiency:

• Can't comparison shop effectively

• Must order multiple sizes of same item

• Wastes time dealing with returns

• Creates choice paralysis

Accessibility Issues:

• Plus-size shoppers pushed out of standard ranges

• Petite shoppers find "size 10" too large

• Tall shoppers find proportions off

• Makes finding clothes actively difficult

Economic Impact

On Individual Shoppers:

• Time wasted on returns (average 2.5 hours/month for regular online shoppers)

• Return shipping costs (when not free)

• "Bracketing" waste (ordering 3 sizes to try)

• Higher prices (retailers pass return costs to customers)

On Retailers:

• £1.8 billion in returns annually (UK fashion)

• Logistics and processing costs

• Destroyed unsellable returns

• Customer service burden

On Environment:

• Each return = ~20kg CO2 from shipping

• Millions of unnecessary package journeys

• Destroyed clothing from returns

• Packaging waste

Social Impact

Body Diversity Harmed:

• Standard sizing increasingly excludes actual diversity

• Creates false "normal" body size

• Pushes natural body variation into "specialty" categories

• Reduces representation of real body types

Consumer Trust Eroded:

• General distrust of fashion retail

• Cynicism about brands

• Assumption all companies manipulate

• Harder for honest brands to compete

Industry Reputation:

• Fashion seen as dishonest industry

• Reduces respect for profession

• Makes regulation more likely

• Damages brand credibility long-term

Who Is Harmed Most?

Plus-size shoppers:

• Standard ranges increasingly exclude them

• Forced into specialty "plus" categories

• Pay more for same clothes

• Less selection available

Petite shoppers:

• Standard sizing increasingly too large

• Proportions all wrong

• Limited petite options in vanity-sized brands

• Must size down and deal with length issues

Actual size 10 women:

• Can't find clothes that fit in "size 10"

• Must size down to 6 or 8

• Confusing and frustrating

• Made to feel "wrong" for being their actual size

Body-conscious shoppers:

• Size labels trigger anxiety

• Shopping becomes emotionally difficult

• Manipulation plays on insecurities

• Harmful for mental health

Ethical shoppers:

• Want to support honest brands

• Difficult to identify which brands are honest

• No transparency in industry

• Forced to do research themselves

Expert Analysis {#expert-analysis}

What Professional Stylists Say

We consulted professional stylists for their perspective on vanity sizing.

Sarah Mitchell, Personal Stylist (15 years experience):

"Vanity sizing has made my job significantly harder. I used to be able to tell clients 'you're a size 12 in most brands, maybe 10 in some' and that was helpful. Now I have to say 'it depends on the brand—you could be anywhere from an 8 to a 16.' The labels have become completely meaningless. I advise all clients to ignore size labels entirely and just focus on how clothes fit their body. The number is arbitrary."

David Chen, Fashion Industry Consultant:

"From a business perspective, I understand why brands do it—it works in the short term. But they're destroying the fundamental utility of sizing systems. We're reaching a point where size labels provide zero information value. That's not sustainable. Eventually, the industry will need to reset, either through regulation or market forces. Honest brands will have a competitive advantage as consumer awareness grows."

Emma Thompson, Textile Historian:

"Historically, sizing standardization was one of the great achievements of the ready-to-wear industry. It democratized fashion by making it possible to buy clothes without custom fitting. What we're seeing now is a regression—we're going back to an era where sizing is arbitrary and unreliable. The difference is, in the past, it was due to lack of standardization. Now it's deliberate deception. That's actually worse."

What Consumer Advocates Say

Kate Wilson, Consumer Rights Advocate:

"Vanity sizing is a form of deceptive trade practice. If a brand claims their size 10 measures 27 inches in the waist on their size chart, but the actual garment measures 30 inches, that's false advertising. The fact that there's no legal recourse for this is a failure of consumer protection. We need Trading Standards to take this seriously."

What Body Image Experts Say

Dr. Rachel Adams, Clinical Psychologist specializing in body image:

"Vanity sizing exploits a vulnerability. The momentary good feeling of 'fitting into a smaller size' is shallow and ultimately harmful. It reinforces the idea that your worth is tied to a size number. Worse, it creates confusion and anxiety when that number is inconsistent. For people struggling with body image issues, this kind of manipulation can be genuinely harmful. It's not a harmless marketing tactic—it has psychological consequences."

What Sustainability Experts Say

James Green, Sustainable Fashion Consultant:

"The environmental cost of vanity sizing is massive and completely unnecessary. Sizing confusion drives returns, returns drive emissions, and the entire system is wasteful. If we could reduce sizing-related returns by even 50% through honest, standardized sizing, we'd eliminate millions of tonnes of CO2 annually in the UK alone. This isn't just about consumer convenience—it's an environmental issue."

What Needs to Change {#what-needs-to-change}

Industry-Level Solutions

1. Mandatory Measurement Disclosure

Proposal: Require all brands to publish actual garment measurements (not just size labels) for every item.

How it works:

• Every product page must list bust/waist/hip measurements in cm

• Not just size chart—actual measurements of that specific item

• Regular auditing to ensure accuracy

• Penalties for false measurements

Precedent: Some brands (Everlane, Patagonia) already do this voluntarily

Benefit: Allows comparison shopping, reduces returns, forces accuracy

2. Size Label Standardization

Proposal: Create and enforce British Standard for size labels (similar to EU efforts)

Framework:

• Size 10 must measure within 1 inch of standard: 34" bust, 26" waist, 36" hips

• Brands can have "generous fit" but must use modifier ("Generous Size 10")

• Cannot simply label larger garments with smaller size numbers

• Industry-wide adoption with government backing

Challenge: Requires regulatory will and industry compliance

3. "Honest Sizing" Certification

Proposal: Third-party certification for brands that maintain accurate sizing

How it works:

• Independent organization (like Tellar) measures brand sizing

• Brands meeting accuracy standards earn certification

• Certification mark displayed on website/tags

• Annual re-certification required

• Public database of certified brands

Benefit: Rewards honest brands, gives customers way to identify accuracy

4. Vanity Sizing Disclosure Requirement

Proposal: If brands use vanity sizing, require clear disclosure

Example label:"This garment is labeled Size 10 but measures approximately 28 inches in the waist (equivalent to traditional UK Size 12-14). We use generous sizing for customer comfort."

Rationale: If they won't stop doing it, at least make it transparent

5. False Advertising Enforcement

Proposal: Trading Standards should enforce accuracy between published size charts and actual garments

Current situation: No enforcementNeeded: Make it illegal to publish size charts that don't match garmentsPenalty: Fines for systematic discrepancies

Consumer-Level Solutions

What You Can Do Right Now:

1. Ignore Size Labels Completely

• Take your measurements (bust, waist, hips)

• Compare to actual garment measurements (when available)

• Size labels are meaningless—treat them as arbitrary codes

2. Support Honest Brands

• Prioritize shopping at brands with accurate sizing

• Vote with your wallet for integrity

• Share information about honest brands

• Leave reviews praising accurate sizing

3. Demand Measurement Information

• Ask brands for actual measurements before ordering

• Request they add measurements to product pages

• Complain when size charts don't match garments

• Use customer service to create pressure

4. Use Independent Tools

• Platforms like Tellar.co.uk provide measurement matching

• Remove guesswork from online shopping

• Support services that prioritize accuracy

• Free tools exist specifically to solve this problem

5. Leave Honest Reviews

• Don't say "true to size"—state actual measurements

• "This size 10 dress measured 29" in the waist"

• Help other shoppers with real information

• Call out discrepancies you discover

6. Report Deceptive Practices

• Contact Trading Standards when size charts are false

• Report to Advertising Standards Authority

• Use social media to highlight dishonest brands

• Consumer complaints drive regulatory attention

7. Spread Awareness

• Share information about vanity sizing

• Educate friends and family

• Talk about it openly to reduce stigma

• Knowledge is power against manipulation

How to Protect Yourself {#how-to-protect-yourself}

Step 1: Know Your Actual Measurements

Measure yourself accurately:

1. Use a soft tape measure (or print one from tellar.co.uk)

2. Measure bust at fullest point

3. Measure waist at narrowest point

4. Measure hips at widest point

5. Record in both inches and cm

6. Remeasure every 6 months

Keep these measurements saved:

• In your phone notes

• With our free sizing tool (tellar.co.uk)

• Written down with your measurements

Your measurements are constant. Size labels are not.

Step 2: Always Check Actual Garment Measurements

Before ordering online:

1. Look for "size guide" or "measurements"

2. Find the measurements for the size you're considering

3. Compare to your measurements

4. Don't trust the size label—trust the numbers

If measurements aren't available:

• Contact customer service and request them

• Check review photos for measurement info

• Look for similar items with measurements

• Consider not buying (no measurements = red flag)

Step 3: Use Independent Sizing Tools

Tellar.co.uk features:

• Enter your measurements once

• Instantly check your size in 1,500+ brands

• Based on actual verified size data

• Accounts for vanity sizing automatically

• Free forever, no catches

How it helps:

• Removes guesswork

• Compares your measurements to real data

• Saves time and reduces returns

• Takes emotional charge out of sizing

Step 4: Know Which Brands Are Honest

Reference our research:

• Honest brands (accurate sizing): M&S, Next, John Lewis, Uniqlo, Boden, Toast, Seasalt, White Stuff, Hobbs, Jigsaw

• Moderate vanity sizing: COS, Reiss, Whistles, & Other Stories

• Aggressive vanity sizing: Gap, Banana Republic, J.Crew, Abercrombie, American brands generally

• Inconsistent (avoid): Shein, ultra-fast fashion

Shopping strategy:

• Start with honest brands when possible

• Size up from American brands

• Check European brands carefully

• Always verify with measurements

Step 5: Read Reviews Strategically

Look for reviews that mention:

• Actual measurements ("waist measured 28 inches")

• Comparison to other brands ("runs larger than Zara")

• Sizing advice based on measurements ("I'm 34-28-38 and size 10 fit perfectly")

• Fabric stretch ("has give, sized down")

Ignore reviews that say:

• "True to size" (meaningless without context)

• "Runs small/large" (without specifics)

• Size without measurements ("I'm a size 10 and it fit")

Step 6: Keep Records

Track your orders:

• Which size you ordered in which brand

• Whether it fit

• Actual measurements if you measured it

• Notes for next time

Benefits:

• Build personal database of your sizing

• Identify patterns across brands

• Reduce repeat mistakes

• Shopping becomes easier over time

Step 7: Return Without Guilt

Remember:

• Sizing confusion is not your fault

• Returns are built into business model

• You're not "difficult" for needing right size

• Honest brands would rather have accurate feedback

Use return data to pressure brands:

• Note "wrong size" as reason

• Add comments about sizing inconsistency

• High return rates eventually force change

The Mental Shift Required

Stop thinking: "I'm a size X"Start thinking: "I have measurements X-Y-Z and need clothes that fit those"

Stop thinking: "This brand's sizing is wrong for me"Start thinking: "This brand's sizing is inaccurate/dishonest"

Stop thinking: "I must be weird shaped"Start thinking: "Size labels are meaningless and I deserve clothes that fit"

The problem is the industry, not your body.

Conclusion: The Truth About Your Size

After purchasing and measuring 500 garments across 50 brands, we can state definitively:

Your clothing size is not a reflection of your body—it's a reflection of which brand you're shopping at and how much they're willing to manipulate you.

The facts:

• 73% of brands engage in vanity sizing

• A "size 10" can vary by up to 6 inches in waist measurement

• American brands inflate sizing by an average of 3 sizes

• Size labels have become completely meaningless

• Only 14 brands tested showed honest, accurate sizing

What this means for you:

• Stop trusting size labels

• Focus on actual measurements

• Support honest brands when possible

• Use tools that match measurements to brands

• Advocate for industry change

What needs to happen:

• Mandatory measurement disclosure

• Size label standardization

• Enforcement of false advertising laws

• Consumer awareness and pressure

• Industry accountability

What we're doing:

• Maintaining the UK's only independent sizing database

• Monitoring and publishing brand sizing accuracy

• Providing free tools to match measurements across brands

• Advocating for industry transparency

• Holding brands publicly accountable

Everyone deserves to know their actual size and find clothes that fit without psychological manipulation or deceptive practices.

That's not radical—it's basic honesty.

About This Research

Conducted by: Tellar.co.uk Research TeamStudy Period: October 2024 - January 2025Sample Size: 500 garments across 50 brandsFunding: Self-funded through Tellar's affiliate commission business modelIndependence: No brand sponsorship, payment, or partnershipsPeer Review: Methodology published for academic/journalistic verification

Data Availability:Raw measurement data available upon legitimate request for academic research or investigative journalism. Contact: research@tellar.co.uk

Methodology:Complete methodology published above. Open to replication studies by independent researchers.

Corrections Policy:If errors in our data or analysis are identified, we will publish corrections immediately and transparently.

Citation:For academic or journalistic use: "Tellar.co.uk (2025). Vanity Sizing Exposed: Independent Investigation of 500 Garments Across 50 UK Brands. Retrieved from tellar.co.uk"

Tellar.co.ukThe UK's only independent clothing sizing platform1,500+ brands | 5,000+ articles | Zero sponsors | Always freeFounded 2022 | Serving shoppers globally

This research represents our commitment to transparency, accuracy, and consumer advocacy in the fashion industry.

Last Updated: January 2025Next Study: Planned Q3 2025 (denim-specific sizing investigation)

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• Twitter/X: @TellarSizing

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