Sister Sizing
Sister Sizes
Your current bra size has "Sister Sizes" - alternate sizes where the cup volume stays the same even though the band size and cup letter changes. This means that even if we don't have your bra size in stock, you can still order a bra that fits you, by choosing the corresponding Sister Size.Find your Sister Size
Your bra size has two Sister Sizes going "up" and "down". "Up" means that the Sister Size is one actual size larger and one letter name smaller than your current bra size. "Down" means the opposite - one actual size smaller and one letter name larger. For example, if you wear a 38B, your Sister Size Up would be 40A, and your Sister Size Down would be 36C. You can wear either one of the Sister Sizes and still have the same cup volume as 38B! The only difference is that you'd probably need to use the furthest or the tightest hook of the bra, instead of the middle one.
Our Sister Sizes Guide
The chart below will help you find your Sister Sizes. Just look for your actual bra size in the middle column.
Sizes in pink are stocked by BackStory.
| 30 Band Size | ||
| Sister Size DOWN | Current Bra Size | Sister Size UP |
| 28DD | 30D | 32C |
| 28DDD | 30DD |
32D
|
| 32 Band Size | ||
| Sister Size DOWN | Current Bra Size | Sister Size UP |
| 30D | 32C | 34B |
| 30DD | 32D | 34C |
| 30DDD | 32DD | 34D |
| 34 Band Size | ||
| Sister Size DOWN | Current Bra Size | Sister Size UP |
| 32B | 34A | 36AA |
| 32C | 34B | 36A |
| 32D |
34C
|
36B
|
| 32DD |
34D
|
36C
|
| 32DDD | 34DD |
36D
|
| 36 Band Size | ||
| Sister Size DOWN | Current Bra Size | Sister Size UP |
|
34B
|
36A | 38AA |
|
34C
|
36B
|
38A |
|
34D
|
36C
|
38B
|
| 34DD |
36D
|
38C
|
| 34DDD | 36DD |
38D
|
| 38 Band Size | ||
| Sister Size DOWN | Current Bra Size | Sister Size UP |
|
36B
|
38A | 40AA |
|
36C
|
38B
|
40A |
|
36D
|
38C
|
40B
|
| 36DD |
38D
|
40C
|
| 40 Band Size | ||
| Sister Size DOWN | Current Bra Size | Sister Size UP |
|
38C
|
40B
|
42A |
|
38D
|
40C
|
42B
|