What Is the Smallest Bra Size?
Many women with small breasts wonder, “What is the smallest bra size?” The truth is, there isn’t one universal smallest size — it depends on finding your correct fit. The smallest bra size could be 28A, 30AA, or even 28AA depending on your body. In the U.S., AA and AAA cups are the smallest standard cup sizes, while 28 is the smallest common band size. Put together, sizes like 28AA are often the smallest bras available.
Understanding Bra Sizing
Bra sizes consist of two parts: the band size (a number) and the cup size (a letter). Here’s how to measure:
- Underbust: Wrap a tape around your ribcage under your breasts. Round to the nearest even number — this is your band size.
- Bust: Measure around the fullest part of your chest.
- Subtract bust from underbust:
- 1″ = A cup
- 0.5″ = AA cup
- < 0.5″ = AAA cup
Remember, cup volume changes with band size. A 28C cup is smaller than a 34C. For best results, try our bra size calculator and size chart.
Smallest Bra Size and Cup Sizes
The smallest commonly sold bra is 28AA. A few specialty brands even make AAA cup sizes. While 26 band sizes may exist, they are extremely rare and usually custom-made. Petite lingerie brands often offer these smaller sizes:
- Little Women Lingerie – known for AAA cups.
- Retailers carries AA and AAA cup bras for small busts.
Is a 28 Band Size Small?
Yes, 28 band is considered small. Most bras start at size 32, so 28 means a petite frame. If 28 is too snug, try sister sizing: move to a 30 band and drop a cup size (e.g. 28A → 30AA).
32A vs 32AA: What’s the Difference?
32AA is one cup smaller than 32A. That’s roughly a half-inch less in bust difference. So if 32A feels too big, 32AA may fit better. You can also try 30A or 30AA to adjust band snugness.
Signs of a Perfectly Fitted Bra
- Band: Snug and straight around the body.
- Straps: Stay in place but don’t dig in.
- Cups: No gaps or spilling.
- Center gore: Lies flat between breasts.
If it doesn’t fit right, try a different size or sister size.
What to Wear if an A Cup Is Too Big
If even A cup bras feel loose, try AA or AAA cup sizes. Brands like Lulalu and The Little Bra Company specialize in petite fits. You can also explore bralettes or wireless bras with flexible sizing.
Size Chart and Tools
Use our online tools for a perfect fit:
Keep in mind: Cup size is relative to band size. That’s why a 28C is smaller than a 34C — even though the letter is the same.
Frequently Asked Questions
What is the smallest cup size?
The smallest standard cup is AA. Specialty brands also offer AAA, which is even smaller. The tiniest common combo is usually 28AA.
Is AAA smaller than AA?
Yes. AAA is smaller than AA, and often used for busts with less than a 0.5” difference between bust and band.
Do small-busted women need to wear bras?
No, it’s personal choice. Some prefer light support or nipple coverage, while others go braless or use bralettes.
Where can I find AAA or 28AA bras?
Check specialty brands like:
