It’s a sure thing Crossword Clue

 Sure, here are some possible answers for the crossword clue "It’s a sure thing":

CERTAINLY (9 letters)

CERTAINTY (9 letters)

GENUINELY (9 letters)

CORRECTLY (9 letters)

NO DOUBT (8 letters)

LOCK (4 letters)

SLAMDUNK (7 letters)

The best answer will depend on the specific context in which the clue is used. For example, if the clue is in a puzzle about sports, then the answer "LOCK" would be the most likely answer.

I hope this helps!