Key Takeaways
| Bust first | The bodice is the hardest part to alter, so the bust decides the size before anything else does. |
| Not your bra size | Measure across the fullest part of the bust in an unpadded bra. Our dresses have a built-in bra. |
| Four numbers | Bust, Waist, Hips and Hollow to Floor. All four barefoot, all four with someone else holding the tape. |
| Heels are already allowed for | We add 2 inches to custom floor-length dresses and dresses with trains. Do not add it yourself. |
| Order timing | Plan on 4 to 7 weeks from order to doorstep for a custom-sized gown. |
Get the bust right and everything else can be fixed. Get the bust wrong and the dress usually cannot be saved, because the bodice is the one part a tailor cannot rebuild without taking the whole gown apart.
That is the entire logic of prom dress sizing, and it is why the size you wear in jeans tells you almost nothing useful.
Why the Bust Measurement Comes First
A skirt can be taken in at the side seams. A hem can be shortened. A bodice with boning, a built-in bra and a fitted lining is a different problem entirely.
The bodice carries the structure
On a strapless or fitted gown, the bodice is doing the work of holding the dress up. Alter it and you move the boning channels, the bra cups and the zip line at the same time. Most tailors will quote heavily for this, and some will decline.
Dress sizes are not comparable between brands
This is not your imagination. As Wikipedia's overview of clothing sizes explains, two size-ten dresses from different companies, or even from the same company, can differ substantially, and sizes have drifted over decades.
Formalwear runs smaller than daywear
Occasion dresses are cut closer to the body than the clothes you wear every day, and they have very little ease built in. Expect to measure into a larger number than you are used to, and treat that as normal rather than as a problem.
The Four Measurements, Taken Correctly
These four are what our custom sizing uses. Take them all barefoot, over light clothing, with someone else holding the tape. Measuring yourself in a mirror introduces errors in every one of them.
Before you start, have:
- A soft tape measure, not a builder's tape
- An unpadded bra
- Light clothing or bare skin, never knitwear
- Bare feet and a hard floor
- Someone else to hold the tape
Bust
Wear an unpadded bra. Relax your arms at your sides, then pull the tape across the fullest part of the bust and around the back at the same height. A padded bra adds up to two inches that the finished dress will not need.
Waist
Find your natural waist, which is the narrowest part of your torso and usually sits about an inch above the belly button. Keep the tape slightly loose so you can breathe, because you will be wearing this for six hours.
Hips
Measure the widest part of the hips, below the natural waist, with the tape level all the way around. Stand with your feet together. Standing with feet apart widens the measurement and produces a skirt that hangs loose.
Hollow to Floor
Stand straight with your feet together, barefoot. Measure from the hollow between your collarbones straight down to the floor. This is the measurement that decides hem length, and it is the one most often taken wrongly in shoes.
Three mistakes that cost the most
Measuring over a thick jumper adds an inch or more to both bust and waist. Measure over light clothing or bare skin, never over knitwear.
Pulling the tape tight to get a smaller number produces a dress you cannot sit down in. The tape should lie flat against the body without compressing it, and you should be able to slide a finger underneath.
Measuring alone in front of a mirror tilts the tape at the back on every single measurement, which is why the numbers come out too small. Ask someone else, even for the ones that feel easy.
Standard Size Versus Custom Size
Both options exist for a reason. The right choice depends on how close your four measurements are to a single column of the size chart.
When a standard size works
If your bust, waist and hips all land within the same size column, a standard size is faster and simpler. Our size chart gives US, UK and EU equivalents in both inches and centimetres.
When custom sizing is worth it
If your measurements straddle two or three columns, custom sizing is not a luxury, it is the difference between a dress that fits and a dress that needs two rounds of alterations. This is common rather than unusual.
The height problem nobody mentions
Standard sizes assume an average height. If you are notably tall or petite, the waist seam of a standard dress lands in the wrong place on your torso, and no amount of taking in at the sides will move it.
Why Custom Sizing Cannot Be Undone
Custom sizing is the strongest reason to order from us and the one thing that carries a real obligation on your side. It is worth being blunt about how that works.
Made to order means made for you
Every dress is cut after you order it, to the measurements you submit. Nothing sits in a warehouse waiting. That is why the production time is 7 to 15 business days for prom dresses rather than immediate.
Wrong measurements are not a returnable fault
We accept returns for quality problems and for sizing that we made incorrectly. We cannot accept a return when the measurements submitted were wrong, because the dress was made exactly as specified and cannot be resold.
What to do if it arrives slightly off
For minor issues we would rather you keep the dress and have it altered locally, and we reimburse part of that cost on a scale that runs from 15 dollars on a dress under 70 dollars up to 65 dollars on a dress over 240 dollars.
Measure twice, a week apart
The simplest safeguard costs nothing. Take your four measurements, write them down, then take them again a few days later with the same person holding the tape. If the two sets disagree by more than half an inch, take a third.
If prom is sooner than seven weeks
Production plus processing plus standard shipping to the United States runs 4 to 7 weeks in total. If your date is closer than that, order from Ready to Ship in a standard size and have it altered locally instead.
Shop the Look
Six A-line gowns, the silhouette that gives you the most tolerance while you are learning your measurements.
Sexy Long V-Neck Sleeveless A-Line Satin Prom Dresses with Split — satin needs the most accurate bust measurement of anything here.
Long Off-The-Shoulder Floor-Length Spaghetti Straps A-Line Satin Prom Dresses with Pockets — straps take some load off the bodice, which is more forgiving.
Long V-Neck Sleeveless A-Line Sequined Backless Prom Dresses — sequin cannot be let out, so order this one closest to your true measurements.
Exquisite Long Sleeveless Floor-Length A-Line Tulle Backless Prom Dresses — tulle absorbs small differences through the skirt.
Elegant Long A-Line Lace Chiffon Floor Length Sleeveless Prom Dresses — chiffon over lace, the most forgiving combination on this list.
Chic Long A-Line Floor-Length Sleeveless V-Neck Chiffon Prom Dresses — a clean chiffon column where the Hollow to Floor measurement does most of the work.
If you are still unsure of your measurements, narrow to A-line prom dresses, the shape with the most tolerance.
Frequently Asked Questions
Is my bust measurement the same as my bra size?
No, and confusing the two is the most common sizing mistake. Measure across the fullest part of the bust in an unpadded bra, because our dresses have a built-in bra and a padded one adds inches the dress will not need.
What size should I order if my measurements fall between two sizes?
Order the larger size if you are using standard sizing, because taking a dress in is far easier than letting it out. If two or three of your measurements straddle different columns, choose custom sizing instead.
Do I add height for my heels?
No. Take Hollow to Floor barefoot, and we add an extra 2 inches to custom-sized floor-length dresses and dresses with trains. Adding your own allowance on top will make the hem too long.
Can I return a dress if the size is wrong?
We accept returns for quality problems and for sizing we made incorrectly, within 30 business days of receipt. We cannot accept a return when the measurements submitted were wrong, because the dress was made to those specifications.
How long does a custom-sized prom dress take?
Prom dresses take 7 to 15 business days to make, plus 1 to 2 business days of processing and 9 to 15 business days for standard shipping in the United States. Plan on 4 to 7 weeks in total.
Which silhouettes are most forgiving if I am unsure of my measurements?
A-line and tulle skirts absorb small differences far better than fitted satin or sequin does. Our A-line prom dresses are the safest starting point, and our guides to prom fabrics and mermaid fit explain why.
About the Author
Emma Whitfield writes about prom, homecoming and bridal dressing for Yesbabyonline, with a focus on fit and fabric. She spends most of her time on the questions that photographs cannot answer: how a fabric moves, where a seam sits, and whether you can still dance in it at midnight. She believes the right dress is the one you forget you are wearing.
