NULAYER › Fit guide › Shapewear for a jumpsuit
Yes, with one adjustmentEvery jumpsuit comes off at the shoulders to use the bathroom; that is the price of a one-piece. With an ordinary shaping bodysuit underneath, that means two garments down to the knees in a stall, and two to pull back up and settle. It is the main reason people give up on shapewear under a jumpsuit.
The NULAYER bodysuit changes half of that. Its hook-and-eye crotch closure opens and closes without taking the bodysuit off, so the jumpsuit comes down, the hooks open, and the bodysuit stays on your shoulders with its straps exactly where you set them. You pull one garment back up, not two. The jumpsuit is still a jumpsuit; the bodysuit stops being a second problem.
A fitted or tapered leg shows the seat the way a pencil skirt does, so the thong is the cut: no edge across the seat, bonded edges that lie flat at the hip. A wide or palazzo leg hides the thigh completely, so the mid-thigh cut can do its job of smoothing the upper thigh, and its leg hem sits far above where the trouser flares.
The waist is where a jumpsuit is tightest, because the waist seam is fixed by the pattern rather than by you. The bodysuit's medium-firm panel smooths the midsection and waist under that seam, and because the bodysuit is held by its straps instead of a waistband, there is no second band to stack on the jumpsuit's.
Jumpsuits with sleeves, wide straps or a square neck cover the bodysuit's straps with room to spare; the deep V sits under a V or scoop neck. Halter, one-shoulder and strapless jumpsuits bare exactly where the straps run, so those are a no, and the halter and one-shoulder pages explain what to wear instead.
A jumpsuit has a fixed rise from shoulder to crotch, and a bodysuit set too short underneath will fight it. Lengthen the straps until the crotch closure sits comfortably and the waist panel is at your natural waist; if the straps at their longest still pull, the size is one band too small. The built-in bra has no compression on the bust, so your own bra fits underneath, straps inside.
Which size: Size by bust and waist. If the jumpsuit is tight at the waist seam, take the larger band when you are between sizes; two tight waists do not add up to a better line.
| Band | US | Bust (in) | Waist (in) |
|---|---|---|---|
| XXS–XS | 0–2 | 30–33.5 | 23–26 |
| S–M | 4–10 | 34–38.5 | 26.5–31 |
| L–XL | 12–14 | 39–41 | 31.5–34.5 |
| 2XL–3XL | 16–20 | 41.5–48 | 35–41.5 |
True to size for most wearers.
Between sizes: the smaller band for maximum smoothing, the larger for all-evening comfort.
No. The bodysuit's straps would show at the shoulders. A strapless jumpsuit needs a strapless bra with a smoothing brief or short; the strapless-dress page has the same answer.
No. The leg hem sits above where wide trousers flare, and the edge is bonded and flat. Under thin white linen, check in daylight, because any edge can shadow through a very thin fabric.
A bodysuit is held by its straps, so it does not roll at the waist the way shorts can. Either one comes down with the jumpsuit in the bathroom; only the bodysuit stays on afterwards.
Written by the NULAYER team and checked against the garment's tech pack. Last reviewed 2026-10-08. Facts on this page: 78% nylon, 22% spandex; machine wash cold, hang dry; designed and made in our own factory in zhejiang, china.