You should have received Form 1099-R for the distribution from your IRA. If you took other distributions besides the QCD, all the distributions are combined in one 1099-R.
Enter the information from the 1099-R into TurboTax exactly as it appears on the 1099-R form, including the taxable amount. After you enter it and proceed through the interview it will ask you a series of questions about the IRA distribution. If the 1099-R has distribution code 7 or 4 in box 7, the IRA/SEP/SIMPLE box is checked on the 1099-R, and you are over 70½ years old, you will come to a screen that says "Transfer to Charity?" On that screen, you will be able to indicate that all or part of the distribution was transferred to charity, and the amount, if the entire distribution was not transferred to charity.
The amount that was transferred to charity will be shown as non-taxable on your tax return. On Form 1040, the full amount of the distribution will be included on line 4a. Only the taxable amount will be included on line 4b, and the notation "QCD" will be on line 4b.
