You can absolutely finish filing a state return after you've already filed your federal. If you're using TurboTax Online, please see below for instructions.
Instructions:
- Login to your TurboTax account.
- In the Welcome Home box, click Visit My Tax Timeline at the bottom.
- In the SOME THINGS YOU CAN DO section, click Add a state.
- Click on the State Taxes tab.
- Click Continue to start or complete your state taxes.
- Click Done with State.
- Continue through the flow to review and file your state taxes.
Please see the following FAQ for more information and instructions if using TurboTax CD/Download. https://ttlc.intuit.com/replies/5269973
