What happens if I file my state return after the 4/15 deadline?

If you expect to receive a refund on your 2024 tax return, there is no penalty for filing after the April 15, 2025 deadline. 

If you expect to owe taxes on your 2024 tax return, you may be charged a penalty for filing after April 15, 2025. You may also be charged interest on any unpaid taxes for each month they remain unpaid.

You can learn how much interest and penalties are here.