Any A cup.
I'd say A or below. But I might be being overly picky, because I prefer smaller over bigger, and I know I"m unusual in that.<br />
So some people might grumble at a C cup, for all I know. Way I see it, if a bra is of any use to someone, then they don't get to claim to be flat chested.<br />
Also, I think it's kinda age dependant, too - before about 15, I think anything over "can still see ribs where there will one day be boobs" would have to argue strenuously to be counted as "flat".
Stop worrying about your chest. They will either grow or not grow. Either way is lovely.
love how you're saying that about a 16yr old.... can you say pedo? XD
Dont worry bout yo boobies...
smaller than you