How to Find Your Size in a Denim Jacket — And Actually Get One That Fits

By Ella Blake, Tellar Stylist

Finding your size in a denim jacket is trickier than it looks — and I say that as someone who has genuinely bought and returned about six of them before finally cracking it. The short answer? Size up from your usual top size, fit across the shoulders and bust first, and ignore the body — it'll look better with a bit of room anyway. But let's go deeper, because there's quite a lot that goes wrong between browsing and wearing.

Why Denim Jackets Fit So Differently

Denim has almost zero give. Unlike a jersey top or a knit cardigan, a denim jacket will not stretch or mould to your body over the course of a day. What you feel in the fitting room is what you're getting, full stop. This means it's genuinely worth taking a few extra minutes to check the fit properly before you commit.

The other thing that catches people out is that denim jackets are structured in a very specific way — they have seam lines, button plackets, and defined shoulder seams that make any misalignment immediately obvious. A poor fit doesn't hide quietly in denim. It announces itself every time you put the jacket on.

The Measurements That Matter Most

Before you start shopping, measure these three things:

Bust — measure at the fullest point across the chest, arms relaxed at your sides. This is your most important number for denim jackets, because the chest seam is non-negotiable once you've bought it.
Shoulder width — from shoulder bone to shoulder bone across the back. Dropped shoulder seams are the number one denim jacket fit problem and they cannot be fixed after the fact.
Upper arm — especially relevant if you have broader or more muscular arms. Denim sleeves are cut quite slim and can be surprisingly restrictive.

Hips and waist matter far less here — denim jackets are typically cropped or hip-length and don't need to close across the body. Focus your energy on what's happening above the waist.

The Golden Rule: Always Size Up

I cannot stress this enough. If you're a 12 in most tops, try a 14 in a denim jacket first. The fabric doesn't give, the cut is boxy by design, and you need enough room to layer underneath — a fine knit, a shirt, even just a substantial T-shirt. A denim jacket that fits perfectly over nothing will be unwearable the moment you add any kind of layer.

My personal fail: I once bought a denim jacket in my actual size, convinced it would be fine because it felt "roomy enough" over a vest top. First cold morning wearing it over a roll neck? Couldn't close the buttons. Couldn't move my arms properly. Returned it immediately. Don't be me.

Body Shape and Denim Jacket Styles

Not all denim jackets are the same cut, and picking the right style for your shape makes a significant difference:

Hourglass — look for a slightly fitted, waist-skimming style rather than a boxy one. A jacket that cinches slightly at the waist will look far more proportionate than one that sits straight from shoulder to hem.
Pear shape — a cropped denim jacket is your friend. It draws the eye upwards and creates balance without adding bulk to your hips. Avoid anything that ends exactly at the widest part of your hips.
Apple or fuller bust — go for a relaxed, open-front style or one with stretch denim in the blend. Avoid heavy embellishments across the chest which add visual bulk where you don't want it.
Petite — a cropped or "trucker" style works best; longer denim jackets can swamp a petite frame. Check product descriptions for "cropped" or look at the model height versus the hem placement in photos.
Tall — check that sleeve length is generous. Many denim jackets are cut for an average frame and if you're 5'9"+, you'll find standard-fit sleeves hit at an awkward point on the wrist.

High Street — The Best Brands for Denim Jackets

I've tested a lot of these. Here's where I'd actually spend my money based on fit, quality, and longevity:

Levi's — genuinely the gold standard for denim jackets. Their Original Trucker Jacket is the one everyone copies and it fits brilliantly once you've found your size. Sizing runs small, so go up one.
Mango — consistently delivers well-designed denim jackets season after season. Their fits tend to be more relaxed and European, which works beautifully if you want something effortlessly thrown-on.
The Gap — underrated for denim. Their Icon Denim Jacket is a classic and comes in a wide size range. Reliable, well-priced, and the sizing is consistent across seasons.
ASOS — brilliant if you need petite, tall, or curve fits specifically. They carry an enormous range of denim jackets and filter properly by fit, which saves a huge amount of guesswork.
Abercrombie & Fitch — much improved in recent years. Their denim is genuinely good quality now and their jackets are cut with a slightly more modern, flattering shape than their old boxy fits.
All Saints — their denim jackets have an edge to them that sets them apart from the usual high street offering. Slightly more structured, a touch darker in wash, and the quality justifies the price point.
Urban Outfitters — great for vintage-inspired and oversized styles if you want something with more personality. Their BDG denim range is particularly well-reviewed and affordable.

Premium and Designer Options Worth Knowing

Citizens of Humanity — one of the best premium denim brands going. Their denim jackets are beautifully made with excellent fabric quality. Worth every penny if you want something that'll last a decade.
Paige — premium American denim that fits incredibly well across the bust and shoulders. Their jackets use slightly softer denim than most, which makes them far more wearable day-to-day.
Calvin Klein — clean, minimal, and consistently well-cut. Their denim jackets are a wardrobe staple at the premium level without crossing into designer price territory.

Two Independent Brands Worth Discovering

Warp + Weft — a size-inclusive American denim brand that goes up to a size 40 and actually cuts the proportions differently for different sizes, rather than just scaling up a sample size. Their denim jackets are exceptional value and fit brilliantly across a wide range of bodies.
Nobody's Child — a sustainable UK brand with a brilliant denim offering. Their jackets are made with more conscious fabrics, cut with a modern, relaxed fit, and the sizing is genuinely true across the range. A great one to know.

Quick Fit Checklist Before You Buy

Shoulder seams sit on your actual shoulder — not drooping onto your arm
You can raise both arms without the jacket riding up excessively
There's no pulling or puckering across the bust when the jacket is closed
Sleeves reach your wrist bone (not mid-forearm)
You can fit a slim layer underneath comfortably

Never Guess Your Denim Jacket Size Again — Use Tellar

Once you've got your measurements, the next challenge is translating them across all the different brands — because a size 12 at Levi's is genuinely not the same as a size 12 at Mango or ASOS. This is exactly what Tellar.co.uk was built to solve.

Tellar is the UK's leading free clothing sizing tool. Measure once — bust, waist, hip, or just your existing size at a brand you already know — and Tellar instantly matches your body to the right size across 1,500+ brands. No size guide rabbit holes. No returns because it "should have fitted."

Use the Store Size Lookup tool to find your exact size at Levi's, Mango, ASOS, Citizens of Humanity, Paige, and hundreds more
Read the Ultimate Clothing Sizing Guide for a full breakdown of how sizing varies across brands
Explore the Ultimate Guide to Jackets & Best Buys for more fit advice across every jacket style
And if you're buying denim all round, the Jeans Trends 2026 guide is worth a read too

It's completely free, works in your browser, and no sign-up is needed. The Tellar Fashion Hub also has a full library of honest, unsponsored style content — written by stylists, not algorithms.

A great denim jacket is genuinely one of the most useful things in your wardrobe — it works over everything from summer dresses to weekend knitwear — but only if it actually fits. Take five minutes to measure up, size up from your usual, and use Tellar to cut out the guesswork across brands. You'll find your perfect one, I promise.