You feel pain-free
A good latch, above all, is pain-free. You may feel a little pain when your baby takes their first suckles (particularly if you've just given birth), but it will generally subside once they take bigger gulps.
You see rounded cheeks
A good sign that your baby has latched onto enough breast tissue, rather than just your nipple, is the fullness of their cheeks. Additionally, you won't be able to see the base of your nipple, only the outer edge of your areola — and a content little face.
You hear swallowing
You might have to listen carefully for this at first. After the first few suckles you'll generally hear a swallow. If all is going well, you shouldn't hear any clicking sounds or air, which might indicate your baby hasn't got enough breast tissue in their mouth.
You see a rounded nipple
A final tip from UK midwife Vicki Scott is to look for a rounded nipple. When your baby is correctly attached to the breast, the nipple should be round, or as it was before the feed. A flattened, misshapen or pinched nipple is a sign your little one hasn’t taken enough breast into their mouth.
If you're unsure of whether your baby is latching on correctly, or simply want some tips, a lactation consultant can provide you with useful information and support.