Yes, you can pay the IRS using a combination of cash (check) and credit card. In TurboTax, when you get to the screen that says How would you like to pay your federal taxes? check Pay by Check. Your payment is due by 4/15/19. You can use the voucher that prints out with your return but you can write the check out for any amount that you choose. Or you can print out a blank 1040-V and fill that out yourself. You can pay the rest with a credit card by going here and choosing a payment processor.
Thanks IsabellaG.
Is there any documentation or written statement needed to the IRS that I have paid my taxes through different methods? Or just curious how the IRS will reconcile the payments from the different methods.
You don't have to have any documentation other than your credit card statement and your banking statement, just like for any other payment that you make. The IRS will credit your account for the tax year in question for any amount you paid by any method.