The following is from a Tax Insider article:
STOP MAKING ESTIMATED TAX PAYMENTS
Once a taxpayer dies, he or she is no longer required to make estimated tax payments. Many well-meaning family members continue to submit the decedent’s quarterly estimated tax vouchers, which is not necessary and may require taking funds out of an investment portfolio, where they could otherwise be growing and earning income for as long as a year.
Not only does Regs. Sec. 1.6654-2(e)(7) indicate no joint estimated tax payments can be made after death and the estate has no liability to make further payments, it makes practical sense that no payments are needed, too. The decedent’s tax year ends on the date of death, so only income received through that date is reportable on the final Form 1040. If the deceased taxpayer was paying an amount each quarter to cover the expected tax liability for that quarter, he or she would no longer need to make those payments after the tax year ends. (Note, however, that the surviving spouse may need to make estimated payments for his or her own tax liability.)
Even if the deceased taxpayer was taking advantage of the prior-year-tax safe harbor in making estimated tax payments and the Form 1040 ends up with a balance due later on, the tax preparer can eliminate filing the Form 2210, Underpayment of Estimated Tax by Individuals, Estates, and Trusts.