General:
* Completed
* Done
* Concluded
* Accomplished
* Ended
* Over
* Through
* Through with
* Wrapped up
Formal:
* Consummated
* Culminated
* Effected
* Finalized
Informal:
* All done
* Through and through
* Out of the woods
* In the bag
Other:
* Exhausted
* Depleted
* Used up
* Spent
The best synonym to use will depend on the specific situation and the tone you want to convey.