About Extended Sizing | Of Mercer

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One wardrobe for
every part of your workweek.
For every woman.

Of Mercer Co-Founders

It started with a problem

When we started Of Mercer three years ago, we set out with the mission of making professional women look and feel their best in and out of the office. But as a small company we had to start...well, small - offering only 7 sizes in our desk-to-dinner styles. But we knew this wasn’t enough.

Over the past few years, it has become abundantly clear that we have many more women who we need to serve. We hear from our would-be customers regularly, asking for us to increase our size range, and it has become all too obvious that many fashion brands are completely ignoring women over size 12, especially if you demand something better than fast-fashion (you should!). So we knew it was time for us to step in and do something about it.

Of Mercer Plus Size

So we found a solution

As a data-centric company (duh, we have Wharton founders) we set out to talk to anyone who would speak to us about the challenges facing plus-size women. We spoke with 50+ professionals (lawyers, bankers, doctors), plus-size experts, models, influencers, and even Janet a high school principal who sat next to Dorie on a plane to Raleigh-Durham. We have enough notes to write a book about fit concerns – arm holes, chest circumference, hem length, and so many more.

With these women we narrowed down the 10 silhouettes to focus on to launch our line, and then we re-fit them through many iterations with a size 16W fit model (Elizabeth Taylor who you may recognize as Melissa McCarthy’s right-hand woman). There are so many subtle, but important, updates from our straight size fit. For example, The Hudson Dress has a sleeve stitch that can be snipped if you want a little more wiggle room for your arm. But this is just the beginning. We are excited to get feedback from our customers and to continue to offer more styles in extended sizes.

Of Mercer Plus

And found ourselves joining a movement
that was bigger than us.

You may recognize some of the faces of our line. Clémentine Desseaux founded the All Women Project, Katie Sturino is a plus-size fashion expert and founder of The 12ish Style, and Julie Henderson launched ALDA with four fellow models (including Ashley Graham) when Ford Models shut down its plus size division, despite it being the most profitable. We are proud to join these, and so many other women in the movement towards size inclusivity and body positivity.


How do your straight and plus sizes differ?

For sizes 00 - 14 we fit on a size 6 fit model and grade the pattern proportionally smaller and larger. However, a size 6 can only be scaled so much without becoming disproportionate. As demand for more sizes grew we knew we needed to create new patterns so as not to lose the fit integrity that we, and our customers, value.

For sizes 14W - 20W we fit on a size 16W fit model. In addition to hiring a dedicated fit model, we adjusted seams, proportions, and hemlines to offer the same superior fit and contemporary style of our existing collection, tailored to sizes 14W-20W.

Am I a 14 or 14W?

Please use the following size chart to help determine which size is best for you. In addition, you'll find product-specific size charts and fit details on each product page.

Straight Size Body Measurements (fit to size 6)

Size Bust Waist Hip
00 XS 32 24 34
0 33 25 35
2 S 34 26 36
4 35 27 37
6 M 36 28 38
8 37 29 39
10 L 38 30 40
12 39.5 31.5 41.5
14 XL 41 33 43

Plus Size Body Measurements (fit to size 16W)

Size Bust Waist Hip
0X 40 32.5 43
14W 1X 44 36.5 47
16W 46 38.5 49
18W 2X 48 40.5 51
20W 50 44.5 53