Side by side
| Training bra / crop top | First bra | |
|---|---|---|
| Structure | None. A single layer or double layer of stretch fabric | Two soft cups, usually non-wired |
| Purpose | Coverage, comfort, getting used to wearing something | Light support and shape |
| Sizing | Age, dress size or S, M, L | Band and cup, such as 30A |
| Fastening | Usually pull-on | Usually hook and eye |
| Stage | Breast buds and early development | When there is enough shape for a cup to fit |
A note on the name
"Training bra" suggests the bra does something to the body. It does not. It is a marketing term, more common in the United States. British shops tend to say crop top, bralette or first bra, and you will see all of them used loosely. Go by what the garment is, not what it is called.
When a crop top is the right choice
- Development has just begun and the chest is tender
- The young person wants something under a school shirt or PE kit
- They want to feel covered when changing for sport
- They are not ready for the fuss of fastenings and straps
Look for soft cotton-rich fabric, flat seams and a wide band that does not dig in. A double layer at the front gives more coverage under white shirts.
When to move to a first bra
- Crop tops no longer give enough coverage or comfort
- There is a measurable difference of about an inch or more between the bust and the ribcage
- The young person asks for one
- Movement during sport is uncomfortable
A first bra should be non-wired or very lightly structured, with adjustable straps and a hook-and-eye back. Measure for band and cup using the teen bra size chart.
There is no required order
Some people wear crop tops for two years. Some go straight to a cup-sized bra because development is fast. Some prefer crop tops well into adulthood. All of that is fine. The stages describe what tends to fit, not what must be worn.
For sport
Breast movement during exercise can be uncomfortable from early on, and discomfort is a common reason for girls to drop out of sport. A soft sports crop top is enough at first. Once there is more to support, a proper sports bra in the right size makes a noticeable difference. See the sports bra calculator.
Having the conversation
- Let the young person lead on timing.
- Offer choices, and let them pick.
- Keep it matter-of-fact. It is a clothing purchase.
- Buy a few, in a size that fits now. They will be outgrown.
More on measuring, fittings and making it a comfortable experience in the first bra fitting guide.
Frequently asked questions
What is a training bra?
A soft, unstructured crop top or bralette worn at the start of breast development. It gives coverage and a layer of comfort. It does not train anything, and the name is mostly American. In the UK these are usually called crop tops or first bras.
At what age do girls need a training bra?
There is no set age. Breast development commonly begins between about 8 and 13. The right time is when the young person wants one, whether for comfort, coverage or because friends are wearing them.
Does wearing a bra early affect development?
No. Wearing or not wearing a bra has no effect on how breasts develop.
Not measured recently? It takes two minutes.
Open the bra size calculator →