Fit guide
Find your fit.
Choose your coverage.
Every POST SWIM suit is made for all women — and designed with surgical scars in mind. Here's how to find the size that fits — and the coverage that feels like you.
Coverage is a choice. So is your size.
Measure
Four quick measurements with a soft tape. Takes about two minutes.
Match your size
Compare your numbers to our chart. Our current styles run true to size. A few earlier styles run one size small — we flag those on the product page, so size up there.
Choose your coverage
Pick the styles built for what you want covered — chest, back, tummy, or none of the above.
How to measure
Two minutes.
One soft tape.
Measure over bare skin or a thin layer. Keep the tape level and snug — not tight.
Bust
Around your chest at its fullest point (or straight across, if you're flat). Wearing a breast form? Measure with it in.
Band line
Directly under your chest, where a band would sit.
Waist
The narrowest part of your torso, usually just above your belly button.
Hips
Around the fullest part of your hips and seat, feet together.
Size chart
X-Small to X-Large
Body measurements, in inches.
| Measurement | X-Small | Small | Medium | Large | X-Large |
|---|---|---|---|---|---|
| Dress size US | 0–2 | 4–6 | 6–8 | 8–10 | 10–12 |
| Bust | 30–32 | 32–34 | 34–36 | 36–38 | 38–41 |
| Band line | 26–28 | 28–30 | 30–32 | 32–34 | 34–36 |
| Waist | 24–26 | 26–28 | 28–30 | 30–32 | 32–35 |
| Hips | 34–36 | 36–38 | 38–40 | 40–42 | 42–45 |
Find your size by bra size
| Bra size | POST SWIM size |
|---|---|
| 30 A/B – 32 A | XS |
| 32 B/C – 34 A/B | XS–S |
| 34 C/D – 36 A/B | S–M |
| 36 C/D – 38 A/B | M–L |
| 38 C/D – 40 A/B | L–XL |
Every style has its own fit notes on its product page — check those too.
Find your coverage
Choose your coverage
Every woman has days she wants more coverage and days she wants less. Whether it's your chest, your back, your tummy or a scar, use this to find the styles made for the coverage you want.
Every suit is made for every woman. This just shows what each one covers.
| Style | Chest coverage | Tummy coverage | Back coverage | Butt coverage | Flat-friendly | Prosthesis-friendly | Shop |
|---|---|---|---|---|---|---|---|
| Lauren One Piece | Yes | Yes | No | Partial | Yes | No | Shop |
| Jessica One Piece | Yes | Yes | Yes | Partial | No | No | Shop |
| Bonnie One Piece Rashguard | Yes | Yes | Yes | Partial | Yes | No | Shop |
| Melanie Rashguard | Yes | Yes | Yes | No | Yes | No | Shop |
| Lolo Top | Yes | No | No | No | No | No | Shop |
| Joyce Bandeau Bikini Top | No | No | No | No | Yes | No | Shop |
| Lynn Tankini Top | Yes | Yes | Partial | No | Yes | Partial | Shop |
| Zoey Bikini Top | Yes | No | Yes | No | No | Yes | Shop |
| Jill Boyshort | No | Yes | No | Yes | No | No | Shop |
| Lily Bikini Bottom | No | Yes | No | Partial | No | No | Shop |
| Sophie Boyshort | No | Yes | No | Yes | No | No | Shop |
| Ashley Bottom | No | No | No | Partial | No | No | Shop |
| Mariella Bottom | No | No | No | Yes | No | No | Shop |
| Rose Classic Bikini Bottom | No | No | No | Partial | No | No | Shop |
| Lisa Swim Skirt | No | No | No | Yes | No | No | Shop |
Full coverage Partial coverage
After a mastectomy or reconstruction?Start with chest coverage, flat‑friendly or prosthesis‑friendly styles.
After a C-section or hysterectomy?Look for tummy coverage.
Prosthesis fit
Wearing a swim form?
Our TruLife 630 Active Flow Swim Form comes in sizes 5–9 and is made for pocketed swimwear, so it sits secure and smooth against your chest.
Made for a swim formThe Zoey Bikini Top, plus the Lynn Tankini Top for a smaller form.
Shopping sale?A few earlier styles also fit a swim form, so check the prosthesis-friendly filter.
TruLife Active Flow size guide
| Swim form size | Bra size | Band size (in/cm) |
|---|---|---|
| 5 | AA – A – B – C | 36/80 – 34/75 – 32/70 – 30/65 |
| 6 | AA – A – B – C – D | 38/85 – 36/80 – 34/75 – 32/70 – 30/65 |
| 7 | AA – A – B – C – D | 40/90 – 38/85 – 36/80 – 34/75 – 32/70 |
| 8 | AA – A – B – C – D – DD | 42/95 – 40/90 – 38/85 – 36/80 – 34/75 – 32/70 |
| 9 | AA – A – B – C – D – DD | 44/100 – 42/95 – 40/90 – 38/85 – 36/80 – 34/75 |
Fit notes
How each style fits
What each piece feels like on, what adjusts, and how much it covers.
Pair it with
Complete the look
Tops and bottoms are sold separately, so you can mix sizes and coverage. Here are a few of our favorite pairings.
Zoey Bikini Top+ Lily Bikini Bottom
Both in City Girl Stripe. Back coverage up top, high-rise below.
Joyce Bandeau or Lynn Tankini+ Rose Classic Bikini Bottom
Pick your top: clean and minimal, or a little more coverage.
Still deciding?
Tell us what you're looking for
We'll help you find your size and your coverage, personally.
Fit FAQs
Good questions
Which styles work if I'm flat?
Look for flat-friendly styles: the Lauren One Piece, Bonnie One Piece Rashguard, Melanie Rashguard, Joyce Bandeau Bikini Top and Lynn Tankini Top.
What if I'm between sizes?
Our current styles run true to size, so go with the size that matches most of your measurements. A few earlier styles run one size small — if the product page says so, size up. Still unsure? Reach out and we'll help you choose.
Can I wear a swim form with my suit?
Yes. The Zoey Bikini Top has pockets made to hold our TruLife swim form, and the Lynn Tankini Top fits a smaller form.
Can I mix sizes on top and bottom?
Yes — our separates are sold individually, so you can choose a different size for each.
What if it doesn't fit?
Swap it for a different size — exchanges are free, with shipping covered both ways. You have 30 days from delivery to exchange or take store credit, or 14 days if you'd prefer a refund (refunds have a $7 return fee per order). Just email sales@postswim.com with your order number, or start it from your account. Suits need to be unworn and unwashed, with hang tags attached and the hygienic liner in place. Items marked Final Sale and orders using a discount of 30% or more can't be returned. Full details on our Shipping & Returns page.