Oh Polly Size Guide

Buying from Oh Polly Without Guessing Your Size

The Oh Polly Size Guide is their official chart that translates UK sizes into body measurements. It's not perfect, but it's the starting point everyone uses. Oh Polly items tend to run small, especially in their stretchier knit pieces and bodycon dresses. Their sizing is based on UK measurements, so if you're coming from US or EU sizing, you'll likely need to size up by at least one size. Their chart lists chest, waist, and hip measurements for each size. Sizes go from 4 to 20 in most styles. Here's what you're actually looking at: UK Size 6: Chest 30-32 inches, Waist 23-25 inches, Hips 33-35 inches

UK Size 8: Chest 31-33 inches, Waist 24-26 inches, Hips 34-36 inches UK Size 10: Chest 32-34 inches, Waist 25-27 inches, Hips 35-37 inches UK Size 12: Chest 34-36 inches, Waist 27-29 inches, Hips 37-39 inches

UK Size 14: Chest 36-38 inches, Waist 29-31 inches, Hips 39-41 inches UK Size 16: Chest 38-40 inches, Waist 31-33 inches, Hips 41-43 inches UK Size 18: Chest 40-42 inches, Waist 33-35 inches, Hips 43-45 inches

UK Size 20: Chest 42-44 inches, Waist 35-37 inches, Hips 45-47 inches The measurements are in inches because that's standard for Oh Polly's charts. If your measurements fall between two sizes, you should go with the larger one. I learned this the hard way with a ribbed midi dress last year. My waist measured exactly at the midpoint between a 10 and 12. The dress arrived and it was basically unwearable — the waistband dug in so hard it left marks that lasted twenty minutes. I exchanged it for a 12 and it fit perfectly. Now I always round up. Here's something most people miss. Oh Polly doesn't just size by circumference. Their cut prioritizes a specific silhouette — fitted through the bust and hips with a narrower waist. If your measurement gaps are uneven, meaning your bust and hips are significantly larger than your waist relative to the chart, the guide will mislead you. In that case, sizing up for your largest measurement and tailoring the rest costs less than dealing with returns.

I also found that their sizing varies between different fabric types. The stretch jersey dresses labeled UK 10 will actually fit closer to a true UK 10 if you're right on the edge of that size. But their woven and non-stretch styles like the lace mini dresses? Those run noticeably tighter through the bust. I tried to order a UK 8 lace dress expecting it to fit my measurements and it zipped with almost no give. I ended up keeping it for one occasion where I didn't need to sit down, but I returned it for the next purchase.

How to Use the Chart Effectively

First, measure yourself correctly. Don't guess or use old measurements. Take your chest at the fullest part, your waist at the narrowest point above your belly button, and your hips at the widest part. Do this while wearing thin clothing or nothing at all. You'll save yourself about 40 percent of return exchanges just by getting accurate numbers. Next, compare each measurement to the chart independently. Don't look for the size that matches just one number. Look for the size where all three measurements fit within range. If you can't find one, pick the size for your largest measurement. Then check the product description for specific fit notes. Oh Polly often adds comments like "snug fit" or "model wears size 8" on individual product pages. These override the general chart. The actual Oh Polly Size Guide page is available directly on their website under the help or FAQ section. It's a simple table. Nothing fancy. Some people screenshot it. Some just keep it open in another tab. I recommend checking it for every single item you add to cart, not just once at the beginning. They update it occasionally when they introduce new size ranges or change their measurement standards.

What the Guide Doesn't Tell You

The biggest gap in the Oh Polly Size Guide is height-to-proportion information. The measurements assume a roughly average proportion. If you're 5'3 and 5'9 at the same weight and measurements, the dress lengths will read differently on you. The shorter version will hit mid-thigh instead of below the knee, which might matter depending on the style. The other gap is stretch recovery. Oh Polly relies heavily on elastane blends. The charts show your static body measurements, not how much the fabric will expand when you put it on. A UK 10 in their high-stretch knit range might comfortably accommodate a UK 12 body, but only if you're mostly comparing waist measurements. The bust and hips don't have the same forgiveness in these fabrics. You still need to match those even if the waist stretches beyond its listed range. Return policy is worth knowing before you order. Oh Polly typically offers 14 to 28 days depending on your region and whether you're a returning customer. Exchanges are usually faster than refunds. If you know you might need a different size, order both sizes and send one back. That's how most people in my experience handle it. The wait for a confirmed size comes with its own risks — restocks sell out fast on popular items.

Reading review photos helps more than you'd expect. Filter reviews by your size if the site allows it. Most buyers who post measurements include photos showing how the garment actually fits on a real body. This catches the variance that the chart never shows. I've caught two bad buys this way where the photos clearly showed the item running a full size small despite the label saying otherwise. The chart itself is reasonably accurate for what it is. It's not going to solve every fitting problem, especially for non-standard body types or when mixing fabric categories. But it eliminates the worst-case scenario of ordering a complete guess. Most people land somewhere within one size of correct after using it as their baseline.