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Size Guide

Size AU/NZ UK US
XS 8A
8B
10A		 30A
30B
32A		 30A
30B
32A
Small 8DD
10B
10C
10D
10DD
12A
12B		 30DD
32B
32C
32D
32DD
34A
34B		 30DD
32B
32DD
32C
32D
34A
34B
Medium 12C
12D
12DD
12E
14A
14B		 34C
34D
34DD
34E
36A
36B		 34C
34D
34DD
34DDD
36A
36B
Large 14C
14D
14DD
14E
16A
16B
16C		 36C
36D
36DD
36E
38A
38B
38C		 36C
36D
36DD
36DDD
38B
38C
XL 16D
16DD
16E
18A
18B
18C
18D		 38D
38DD
38E
40A
40B
40C
40D		 38D
38DD
38DDD
40A
40B
40C
40D
Size AU Size UK Size Waist (cm)
XS04-0600-0260
Small08-1004-0664
Medium12-1408-1068
Large16-1812-1472
XL20-2216-1876
2XL24-2620-2280
Size Waist (cm) Waist (in)
2XS / (Size 4/8)53-5621-22
XS / (Size 8/12)57-6623-26
Small67-7627-30
Medium77-8631-34
Large87-9735-38
Extra Large98-10739-42
2XL108-11543-45
3XL116-12546-49
4XL126-13350-52
5XL134-14353-56
6XL144-15057-59
Size Waist (cm) Waist (in)
4XS (Age & Size 3-4)40-4415-17
3XS (Age & Size 5-6)45-5118-20
2XS (Age & Size 7-8)52-5921-22
XS (Age & Size 9-11)60-6923-26
S (Ages & Size 12-14)70-7627-30
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    Boxer Brief - Yacht Rock Vol. 2 - Bamboo Underwear Limited Edition - Yacht Rocks! Brief - London Smoke - Bamboo Underwear New! Classic cut Briefs
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  • Melange Range

    The Melange Collection delivers premium bamboo comfort in heathered Grey and Orange.

  • Mojito Women's Matching Set

    Refreshingly comfortable.

  • New Release - Briefs

    Comfort in a classic cut.

  • Socks - Back In Stock!

    Comfy & Durable 🌿

  • NiteKnit Sleepwear

    Engineered for Rest & Recovery
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Boxer Brief - Yacht Rock Vol. 2 - Bamboo UnderwearLimited Edition - Yacht Rocks!Brief - London Smoke - Bamboo UnderwearNew! Classic cut Briefs
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    Discover The Range
New Matching Set - MojitoFlow Forward - Period Underwear
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    Junior Trunk
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Brief - Scorpions - Bamboo UnderwearBrand New Briefs. Classic Cut.NiteKnit™ Sleepwear
  • Boxer Brief Sports
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  • X-Cup Cricket Underwear
- Model:BabaCloud Mesh SportBoxer Brief Sport - Fire Balls - Bamboo Underwear - Model:IvanBest Seller
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[EXP-A] Women's SmoothFit Thong - Espresso-Tini - Bamboo Underwear - Model:ElkeSmoothFit Thong- Model:MakoSmoothFit Bra
  • Body Shorts
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[EXP-A] Women's Underwear Body Short in Black - Model:YolandaBody Short- Model:KymberleeBoyleg
  • Full Brief
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Women's Period Full Brief - Bamboo Underwear - Model:ArmaniPeriod Full BriefPeriod Bikini Brief
  • Crew Sock
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  • No Show Sock
Women's SmoothFit Bikini Brief - Navy - Bamboo Underwear - Model:EmilyMatching SetsNudes
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About Us

Step One is a leading direct-to-consumer online retailer for underwear. Step One offers an exclusive range of high quality, organically grown and certified, sustainable, and ethically manufactured underwear that suits a broad range of body types. Step One has transformed the underwear market with an innovative design and cult-like following and has quickly grown into a multinational company operating in Australia, the US and the UK.

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