Very sorry for your loss.
Follow these steps to start a return for the decedent:
Open (continue) your tax return.
(To do this, sign in to TurboTax and click the orange Take me to my return button.)
2. Click the Personal Info Tab
3. Click Edit by your Name (or Your Spouse's Name)
4. Go to 3. A few other things we need to know
At "I'm preparing this return for [Name], who has passed away." Click Yes (See the attached screenshot below. Click to enlarge.)
In order to claim the refund you must fill out Form 1310 Statement of Person Claiming Refund Due a Deceased Taxpayer and meet the qualifications listed on the form.
After you've filled out the return, search for Form 1310 inside your program and click the "Jump to" link. This will take you to the Complete a Claim for Refund screen. Answer Yes and follow the onscreen instructions.
The chore of filing the taxpayer's final return usually falls to the executor or administrator of the estate, but if neither is named, a survivor must do it. The return is filed on the same form that would have been used if the taxpayer were still alive, but "deceased" is written after the taxpayer's name. The filing deadline is April 15 (April 18 for Tax Year 2016) of the year following the taxpayer's death.
If married, the executor usually files a joint return, but the surviving spouse can file it if no executor or administrator has been appointed.
If an executor or administrator is involved, he or she must sign the return for the decedent. When a joint return is filed, the spouse must also sign. When there is no executor or administrator, whoever is responsible for filing the return should sign the return and note that he or she is signing "on behalf of the decedent." If a joint return is filed by the surviving spouse alone, he or she should sign the return and write "filing as surviving spouse" in the space for the other spouse's signature.
If a refund is due, there's one more step. You should also complete and file with the final return a copy of Form 1310, Statement of Person Claiming Refund Due a Deceased Taxpayer. Although the IRS says you don't have to file Form 1310 if you are a surviving spouse filing a joint return, you probably should file the form anyway to head off possible delays.
Note that you can e-file a return for the deceased. If the return has a refund, you can still e-file the tax return and mail Form 1310 separately or you can mail the form with the complete tax return.