Yes, you can e-file your 2021 amended tax returns. If you used TurboTax to prepare Form 1040-X, follow the software's instructions to e-file the amendment. If you owe money with the amendment, you can pay by credit card or direct debit, or if you want to send in your money by check, then choose to pay by check and the program will print a payment voucher to send in with your payment.
