A 34E is cut differently by every brand. Bands stretch more or less, cups run shallower or deeper, and some retailers still measure with outdated methods. These guides are independent: we do not sell bras, so we can say what a retailer will not.
How the big chains size and fit, and how to check the size you are given.
How the M&S bra fit tool and in-store fitting work, and what to do if the size you were given feels wrong.
John Lewis John Lewis Bra Fitting ServiceWhat the service covers, how to book and who it suits best.
Boux Avenue Boux Avenue Bra SizesSize range, in-store fitting and where the range stops.
Primark Primark Bra SizingWhat you get at the budget end: size range, fit and where the limits are.
Ann Summers Ann Summers Bra SizesWhat sizes Ann Summers offers and how its fashion styles fit.
British brands for D cups and above, all in UK sizing.
The D-cup-and-up specialist: size range, fitting approach and who it suits.
Freya Freya Bra Sizing: Do Freya Bras Run Small?How Freya sizes, how its moulded and unlined styles differ, and how to choose.
Panache Panache Bra Sizing: Do Panache Bras Run True to Size?Panache lingerie and Panache Sport sizing, and its reputation for firm bands.
Curvy Kate Curvy Kate Bra SizingSize range, fit character and how Curvy Kate compares with other full-bust brands.
How fittings at M&S, John Lewis, Bravissimo, Rigby & Peller and independents differ, and who each suits.
Buying Where to Buy Bras in Unusual SizesSmall bands, large cups, large bands and small cups: where each is actually stocked.
Buying How Much Should a Good Bra Cost?What you get at each price level in the UK and how to judge value.
Sister Sizes Sister Size Chart & CalculatorPick your size and see which neighbouring sizes hold the same cup volume on a tighter or looser band.
Why the same size fits differently. There is no enforced UK standard for bra sizing. Each brand builds its own patterns, so your calculated size is a starting point in every shop. If a new brand feels a little off, a neighbouring sister size is usually the first thing to try.