I have a girlfriend that I support and she is a stay at home mom I was wondering if there is a tax break for that and if there is how to do it?

[Zbucklyo]

You may be able to claim your girlfriend as a dependent on your taxes if the following are true:

(1) She lived with you for all of 2017.

(2) She had less than $4,050 in income.

(3) You provided more than half her support.

If the child is your biological child, you can file as Head of Household and claim the child as a dependent as well.

EDITED per Sweetie Jean comment.

[SweetieJean]

(3) You provided more than half of HER support.