Sister sizing means different bra sizes can share the same cup volume, but with different band lengths. It’s a way of moving sideways across the size chart to improve comfort without changing your actual cup size.

How it works –

Go up a band size → go down a cup size to keep the same volume.

Go down a band size → go up a cup size to keep the same volume.

Examples:

30DD, 32D, 34C, 36B all have the same cup volume.

32F, 34E, 36DD are also sister sizes.

If you wear a 34C and the band feels too tight → try a 36B.

If you wear a 34C and the band feels too loose → try a 32D.

If you wear a 36D and the band feels too loose → try a 34DD.

If you wear a 32E and the band feels too tight → try a 34DD.

If you wear a 34B and the band feels too tight → try a 36A.

If you wear a 32DD and the band feels too loose → try a 30E.

👉 In every case, the cup size/volume stays the same — only the underband changes to adjust how snug the bra feels.

Why it matters – Sister sizing is helpful if:

The cups fit but the band doesn’t.

You’re between band sizes.

You’re shopping across brands, since sizing can vary.

At Somewhere Never, my bras feature extra adjustability in the band, so there’s usually more flexibility than in standard bras. But if you’re ever unsure, you can always reach out to me directly at hello@somewherenever.com
for personalised sizing advice — I’ll help guide you to the best fit.

Alpha sizing is when bras are sized in general categories like XS, S, M, L, XL rather than specific band-and-cup numbers (like 34B or 36C). It works especially well for bralettes and non-wired styles, since the fabrics and elastics stretch to accommodate a range of bodies.

Standard alpha sizing – Usually runs from XS–XL, which can feel limiting for people whose proportions don’t fall neatly into those ranges.

Extended alpha sizing – Expands the categories with extra in-between sizes (e.g. XS+, S+, M+), or by offering multiple bust-volume options within the same band size. This allows a more inclusive fit without requiring every possible numeric size.

At Somewhere Never, my current collections use alpha sizing (XS–XL) with large back adjusters for flexibility. But I’m now moving towards traditional bra sizing (34B, 36C, 32DD, etc.), since it ensures a more precise fit. Customers will still benefit from adjustability in the back, but with the accuracy of band-and-cup sizing for the best possible fit.

Measuring yourself is the first step to finding a bra that fits comfortably and supports properly. All you need is a soft tape measure and a mirror.

Band size – Wrap the tape snugly around your ribcage, directly under your bust. Make sure it’s level all the way around and not digging in. This measurement (in inches) is your band size — round up if it’s an odd number.

Example: If you measure 33 inches, try a 34 band.

Bust size – Wrap the tape around the fullest part of your bust, keeping it straight across your back and not pulling too tightly.

Cup size – Subtract your band size from your bust measurement. Each inch difference equals one cup size (1" = A cup, 2" = B cup, 3" = C cup, and so on).

Example: If your band is 34 and your bust is 37, the difference is 3 inches → 34C.

👉 This gives you a starting point, not an exact science. Breast shape, fabric choice, and brand sizing all play a role, which is why trying on is key.

At Somewhere Never, you can also use the bra size calculator on my Fit page, where you simply enter your two measurements and it will suggest your best starting size. My bras are designed with extra adjustability in the band and straps, so they can flex with slight differences in measurement. And if you’re ever unsure, you can always reach out to me at hello@somewherenever.com
for personalised advice.

Not always. Bra sizing isn’t fully standardised across the industry, so a 34C in one brand might feel more like a 34B or 34D in another. Differences in fabric, construction, stretch, and grading methods can all change how a size fits.

Fabric – A rigid embroidered tulle bra will fit more snugly than a stretchy jersey bralette in the same size.

Construction – Cut-and-sew bras shape differently than moulded cups, even in the same labelled size.

Brand grading – Some brands design around a “fit model” at a particular size (e.g. 34B) and then scale up or down, which can affect consistency in larger or smaller sizes.

What to do:

Use your usual size as a starting point, but don’t be surprised if you need a sister size in certain brands.

Focus on how the bra feels — the band should sit snug, the cups should contain without gaping or spillage, and straps should stay in place.

At Somewhere Never, I’m moving toward traditional band-and-cup sizing to give the most precise fit possible. My bras also have generous adjustability in the back, so even if you fall between sizes, you’ll usually find a comfortable fit. And if you’re unsure, you can always contact me at hello@somewherenever.com
for advice on how my sizing compares to what you usually wear.

Bra sizing systems vary across countries, and the biggest differences are in band numbers and how cup letters progress after D.

UK sizing – Band measured in inches (e.g. 32, 34, 36). Cup letters continue with doubles: DD, E, F, FF, G, GG, etc.

US sizing – Similar to UK, but usually skips the double letters after D. A UK 34E = US 34DDD/F.

EU (Continental) sizing – Band measured in centimetres (e.g. 75, 80, 85 instead of 34, 36, 38). Cups progress more straightforwardly: A, B, C, D, E, F.

French (FR) & Italian (IT) sizing – Use EU cups but add +15 (France) or +10 (Italy) to the band number.

👉 Conversion examples (from smaller to larger bands):

UK 30F = US 30G = EU 65G = FR 80G = IT 0G

UK 32DD = US 32DDD/F = EU 70E = FR 85E = IT 1E

UK 32E = US 32DDD/F = EU 70F = FR 85F = IT 1F

UK 34B = US 34B = EU 75B = FR 90B = IT 2B

UK 34C = US 34C = EU 75C = FR 90C = IT 2C

UK 36B = US 36B = EU 80B = FR 95B = IT 3B

At Somewhere Never, I’ll be using the UK/US system (band in inches, cup letters with doubles), since it’s the most widely understood for fashion-led lingerie. If you’re unsure how your usual size converts into my bras, you can always email me at hello@somewherenever.com
and I’ll help you find the right match.

Yes — your bra size isn’t fixed for life. It can change many times depending on your body and lifestyle.

Weight changes – Gaining or losing weight can affect both your band size and cup volume.

Hormonal shifts – Puberty, pregnancy, breastfeeding, menopause, or even your monthly cycle can change breast tissue density and fullness.

Age – Over time, natural changes in skin elasticity and breast composition may alter how bras fit.

Exercise & muscle tone – Building chest or back muscles can change your underbust measurement, while certain high-impact activities may affect bust shape.

👉 This is why it’s important to re-measure regularly and not assume the size you wore years ago still fits perfectly today.

At Somewhere Never, I design bras with generous adjustability in the back bands and straps, so they can adapt with you through natural fluctuations. If you’re unsure whether your size has changed, you can use the Fit page calculator on my site to get a new starting size, or email me at hello@somewherenever.com
for personalised advice.

It’s very common to fall between sizes — maybe your underbust measures closer to a 33 (between a 32 and 34 band), or your bust measurement doesn’t land exactly on a cup size. Here’s how to approach it:

If you’re between band sizes –

Example: You measure 33" underbust. Try both a 32D (tighter band) and a 34C (looser band). Both have the same cup volume, but the band feel will differ.

A firmer band = more support. A looser band = more comfort.

If you’re between cup sizes –

Example: You’re measuring close to a C/D line. Try both a 34C and 34D to see which feels better.

If your bust is fuller at the top, the larger cup will help prevent cutting in. If you have less upper fullness, the smaller cup may sit more smoothly.

If you’re choosing between fabric types –

Jersey or mesh bras (with Lycra) have more stretch, so you can often go with the smaller size and still feel comfortable.

Rigid embroidered tulle (like I use at Somewhere Never) has no stretch, so if you’re in between sizes, I usually advise going up a cup size. That way, the cup edge won’t dig in, and the embroidery will lie cleanly on the skin.

If you’re balancing comfort vs shape – Some people prefer a snugger fit for lift, while others prefer a softer fit for ease. Both are valid — the right choice is the one you’ll actually wear.

At Somewhere Never, my bras are designed with large back adjusters and flexible strap settings, which give more wiggle room between sizes. So even if you’re not an exact match, you can usually find a comfortable fit. And if you’re unsure, you can always email me at hello@somewherenever.com
— I’ll happily help you choose the best option.

It’s easy to confuse sister sizing with cup volume — but they’re not the same thing.

Cup volume – This refers to the actual capacity of the cup, or how much breast tissue it can hold. A 34C cup has more volume than a 34B, and less volume than a 34D. The cup gets bigger or smaller as the letter changes within the same band size.

Sister sizing – This is when the same cup volume is carried across different band sizes. For example, a 34C, 32D, and 36B all have the same cup volume, but the band length changes.

👉 Examples:

A 34C and 34D do not have the same cup volume — the D cup is larger.

A 34C and 32D do have the same cup volume — the only difference is the band length.

At Somewhere Never, I talk about both because they affect how my bras fit:

If you’re unsure about cup volume → move up or down a letter.

If the band feels off but the cup fits → try a sister size.

This distinction is what helps you find the sweet spot where the cup feels right and the band is supportive. And if you’re still not sure, email me at hello@somewherenever.com
and I’ll help work it out with you.