Size 36O Bikinis
Also labeled UK 36K and EU 80O
Holding an O cup on a mid-to-larger band takes a bikini top sized like a bra, which is what 36O gives you. Check the fit dry and again after a swim, since wet fabric can relax. Compare brands and labels in our Cup-Sized Bikini Size Chart.
When a 36O Bikini Band Rides Up
A hook band holds the same setting every time, which many shoppers with a mid-to-larger band find easier to keep level. The band should sit at the same height at the front and back, roughly in line under your bust. Set the band before you touch the straps, since the straps can only fine tune the fit.
Check the top from the side in a mirror. On a mid-to-larger band, the band should sit level from front to back, and the cups should line up with your bust rather than sitting high.
Cup Depth in 36O Bikini Tops
An O cup often needs a wider cup base as well as more depth, so check where the cup meets your side. Very deep cups put more weight on the straps, so the band needs to carry its share for the straps to feel comfortable. The middle of the top should rest near your chest, not float away from it.
In UK sizing, look for 36K. UK charts stop at K for this cup, since they double letters lower down.
Tie Backs and Hook Bands in 36O
Tie backs can be set to any length, which helps if you sit between band sizes. The trade-off is that a knot can slip once it is wet, especially under an O cup. A hook band holds the same setting every time, so many shoppers in 36O find it easier to keep level.
Bras in this size: our 36O bras.
Frequently Asked Questions About Size 36O Bikinis
How does 36O convert to UK and EU bikini sizes?
UK labels print 36K and EU labels 80O, because the US O and the UK K are the same cup. Check which system each brand uses.
Should the straps hold up a 36O bikini top?
No. The band should do most of the work, and the straps only steady the cups. If you need tight straps in 36O, the band is likely too loose.
How should a 36O bikini top feel after swimming?
It should feel close to how it felt dry, with the band level and the cups still covering you. If the band feels loose after a swim, it was probably a little loose to begin with, and on a mid-to-larger band that shows quickly.
Is it normal for 36O to fit differently between bikini brands?
Yes. Brands cut bands and cups differently, so a 36O top can feel firmer in one style and roomier in another. Use each brand's chart and judge the fit on you.
How can I check a 36O bikini top fit at home?
Put the top on, lean forward to settle into the cups, then stand and check the band in a side mirror. Raise your arms and twist, then look for movement at the band or spilling at the edges.
Does a 36O bikini top need wide side coverage?
Yes, usually. With an O cup, tissue can slip out near the underarm when you move, so look for cups that reach back toward your side.