Big blind all in with less than bb - what is needed to call?

[JereLock]

Based on the fact that it was folded to you and theres no one left to act after you. If you were the first one to act after BB, you'd put in the normal 10 chip BB, and then if everyone else folded, 3 would be returned to you before the flop. Same thing.

[Crysan]

There's still the sb to act after the button.

[smbruin22]

as a few said, if UTG goes all-in with 7 but BB is 10, you on button must put in 10, and the big blind gets in for free, so you don't get 3 back.... if you're big blind and no one else called then you'd get 3 back

if one or more others call,
then you're in the hand for 10 (unless there was raise)