I get past step 3 in filing return. I get the message that IRS has not finalized forms. Is this because my mother died at the end of last year?

The message isn't referring to how you filled out the form or anything related to you specifically.  It means that the IRS hasn't finalized the actual IRS form.  In other words, anyone using the same form will get that same message.  Once the IRS has finalized the form, then it will allow your return to be filed (unless you have to fill in something additional on the form due to changes made by the IRS).

When a person passes away, someone else has to claim any refund or pay any tax balance due a deceased taxpayer. This requires Form 1310. This form will be ready soon, but is not ready as of this writing.

To check on the availability, search for Form 1310 here: IRS forms availability table for TurboTax individual Tax Forms.

Our condolences for your loss. You may wish to review this resource for more tax guidance: Death in the Family.

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