Old Navy Sizing: Does It Run Big? Your Complete Guide to Getting the Perfect Fit

Yes, Old Navy sizing generally runs large - most customers find they need to size down by one full size, particularly in their tops and dresses, making it brilliant value for those who typically struggle to find well-fitting clothes in standard UK sizing. As someone who's spent years helping women navigate the minefield of international sizing, I can tell you that Old Navy's generous fit is both a blessing and a potential pitfall if you're not prepared.

Old Navy, the American casual wear giant, has become increasingly popular with UK shoppers seeking affordable, comfortable basics. However, their sizing philosophy differs significantly from what we're accustomed to here in Britain, and understanding these differences is crucial for online shopping success.

Understanding Old Navy's Sizing Philosophy

Old Navy deliberately cuts their garments with a relaxed, comfortable fit in mind. This American approach to sizing means their small often equates to a UK size 10-12, whilst their medium can accommodate sizes 12-14. I've found this particularly pronounced in their knitwear and casual dresses, where the generous cut allows for layering and movement.

The brand's denim, however, follows a slightly different pattern. Their jeans tend to run true to size in the waist but generous in the thigh and hip area. This makes them excellent for pear-shaped figures who often struggle with gaping waistbands in other brands.

How Old Navy Compares to UK High Street Favourites

When comparing Old Navy to beloved UK retailers, the differences are stark. Zara - known for their European slim-fit cutting - typically runs 1-2 sizes smaller than Old Navy. If you're a size 12 in COS, you'll likely need a size 10 or even 8 in Old Navy tops.

H&M, despite being Swedish, follows European sizing conventions and runs significantly smaller than Old Navy. Meanwhile, ASOS - our go-to for trend pieces - varies wildly depending on the brand they stock, but their own-label pieces typically run smaller than Old Navy.

M&S sizing, beloved for its consistency, runs approximately one size smaller than Old Navy across most categories. Next follows similar British sizing standards, meaning their size 12 equates to roughly an Old Navy size 10.

Premium Brand Comparisons

For those familiar with premium brands, Whistles runs significantly smaller than Old Navy, with their size 12 being closer to an Old Navy size 8-10. Jigsaw follows similar European sizing, whilst Reiss - known for their structured pieces - cuts even smaller, particularly in their tailored items.

Designer and Luxury Comparisons

In the luxury realm, brands like Max Mara follow Italian sizing conventions, running much smaller than Old Navy. A Max Mara size 44 (UK 12) would typically correspond to an Old Navy size 8 or even 6, depending on the item.

Category-Specific Sizing Insights

Tops and Blouses: Size down one full size from your usual UK size. Old Navy's generous armhole and body width accommodate American sizing preferences.

Dresses: The oversizing is most pronounced here. I recommend going down 1-2 sizes, particularly in their casual jersey dresses.

Jeans: These run closer to true size in the waist but generous in the seat and thighs. Perfect for curvy figures who struggle with UK high street denim.

Knitwear: Old Navy's jumpers and cardigans are cut for layering, so size down unless you prefer an oversized look.

Unique Brand Recommendations

For those seeking similar value with better UK sizing, consider Everlane - their transparent pricing and ethical production make them excellent for conscious consumers, though they run slightly large too. Arket offers Scandinavian minimalism with more consistent European sizing.

My Professional Styling Tips

When shopping Old Navy online, always check the specific measurements provided rather than relying solely on size charts. Pay particular attention to bust, waist, and hip measurements, as these vary significantly from UK standards.

For petite figures, Old Navy's regular sizing might be overwhelming - their XS often works better than a UK size 8 would suggest. Conversely, plus-size shoppers often find Old Navy more accommodating than UK alternatives.

Consider the fabric content carefully. Cotton-rich items will have less stretch and may feel looser, whilst pieces with elastane will provide more structure despite the generous cut.

Never Guess Your Size Again with tellar.co.uk

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Plus, there's the Tellar Fashion Hub - a library stacked with free posts from top stylists. Honest. Unbiased. Independent and always free. Style advice, top picks, and best brands all in one place.

For more sizing insights, check out these helpful guides:

The Bottom Line

Old Navy's generous sizing makes it an excellent option for comfortable, affordable basics, but preparation is key. Size down confidently, pay attention to measurements, and don't be afraid to experiment. With their excellent return policy and Tellar's precise sizing tool, finding your perfect fit has never been easier.

Remember, great style isn't about the label - it's about how clothes make you feel. Old Navy's accessible pricing and comfortable fits make them worthy of consideration in any well-rounded wardrobe, provided you understand their unique approach to sizing.