Get your taxes done using TurboTax

as of 2015 October, on turbotax online if you need to add the 2024 paid amounts with your Extension request, Navigate to the location as shown below:

Step 1:

Under the Federal tab >> Deductions & Credits >> Deductions and credit summary

Step 2:

Scroll down to and click on "Add more tax breaks"   

Step 3:

Scroll down to and click on "Estimates and Other Taxes Paid" >> "Income Taxes Paid" >> Start

This will open the "Payments with Extension" tab

Step 4:

Here, just click on the "Start" for your 2024-federal or 2024-state buttons and enter the amounts you've paid for either one of them respectively 

Hope this helped.