I am getting a very small refund but it will not cover the filing cost and I cannot afford it until after the due date. I am not sure what to do.

You can file an extension.

 

IRS extensions for tax year 2021 must be filed on or before April 18, 2022 for domestic taxpayers.

It isn't possible to file a post-deadline extension.

Keep in mind: An extension doesn't give you extra time to pay your taxes — but it will keep you from getting a late filing penalty. (You'll still owe interest if you pay after the deadline).

1. Open your return in TurboTax Online.
   (To do this, sign in to TurboTax and select Pick up where you left off).
2. Select File an extension at the bottom of the column on the left side of the screen.
   • If you don't see the File an extension button in Step 2 above, search for extend using your product's search function and select the Jump to link at the top of your search results.
3. Follow the on-screen instructions to e-file your extension.

Note: If you're paying additional taxes owed with direct debit, you'll need to provide your 2020 AGI for verification purposes (if you didn't file a 2020 return, enter 0 as your AGI).

There is no penalty if you are getting a refund.