Size Guide

If you need personalised help choosing your size, please contact our team at contact@naiabeach.com or via the online chat — our fit experts love talking swim and are always happy to help.

If you fall between sizes, we recommend sizing up for the most comfortable fit.

---

Find Your Size (UK)

Bust (cm)	Waist (cm)	Hips (cm)	Recommended UK Size
76 – 82	61 – 64	86 – 90	6
82 – 86	64 – 67	90 – 94	8
86 – 91	67 – 72	94 – 98	10
91 – 96	72 – 77	98 – 103	12
96 – 102	77 – 82	103 – 108	14
102 – 107	82 – 87	108 – 113	16
107 – 112	87 – 92	113 – 118	18

---

Women’s Swimwear

Bikini Tops

UK Size	Bust (inches)	Bust (cm)	Cup Guide
6	30 – 32	76 – 82	A – B
8	32 – 34	82 – 86	B – C
10	34 – 36	86 – 91	C – D
12	36 – 38	91 – 96	D – DD
14	38 – 40	96 – 102	DD – E
16	40 – 42	102 – 107	E – F
18	42 – 44	107 – 112	F – FF

---

Bikini Bottoms & Briefs

UK Size	Waist (inches)	Waist (cm)	Hips (cm)
6	24 – 25	61 – 64	86 – 90
8	25 – 26	64 – 67	90 – 94
10	26 – 28	67 – 72	94 – 98
12	28 – 30	72 – 77	98 – 103
14	30 – 32	77 – 82	103 – 108
16	32 – 34	82 – 87	108 – 113
18	34 – 36	87 – 92	113 – 118

Different styles offer varying levels of coverage, so please bear this in mind when selecting your preferred fit.

One-Piece Swimsuits

UK Size	Bust (cm)	Waist (cm)	Hips (cm)
6	76 – 82	61 – 64	86 – 90
8	82 – 86	64 – 67	90 – 94
10	86 – 91	67 – 72	94 – 98
12	91 – 96	72 – 77	98 – 103
14	96 – 102	77 – 82	103 – 108
16	102 – 107	82 – 87	108 – 113
18	107 – 112	87 – 92	113 – 118

Some one-piece styles feature our trademark Subtle Sculpt, designed to offer comfortable stomach control and gentle shaping while maintaining a smooth, flattering silhouette.

Certain styles also include removable pads, built-in cups, or hidden support shelves for additional support.

 

Women’s Beachwear

Our beachwear is designed with a relaxed, effortless fit to complement our swim collection.

UK Size	Bust (cm)	Waist (cm)	Hips (cm)
6	76 – 82	61 – 64	86 – 90
8	82 – 86	64 – 67	90 – 94
10	86 – 91	67 – 72	94 – 98
12	91 – 96	72 – 77	98 – 103
14	96 – 102	77 – 82	103 – 108
16	102 – 107	82 – 87	108 – 113
18	107 – 112	87 – 92	113 – 118

International Size Conversion

Size	UK	US	EU	AUS
XS	6	2	34	6
S	8	4	36	8
M	10	6	38	10
M	12	8	40	12
L	14	10	42	14
L	16	12	44	16
XL	18	14	46	18

How to Measure

Use a soft measuring tape and measure directly against your body while wearing light clothing or swimwear.

Bust
Measure around the fullest part of your bust while keeping the tape level across your back.

Waist
Measure around the narrowest part of your waistline.

Hips
Measure around the fullest part of your hips while keeping the tape level.

Need Help?

If you have any questions, please contact our fit experts via the online chat — they simply love talking swim and will be happy to assist you in finding your perfect NAIA fit