Where can I enter income from a K-1 (1041) on my son's return?

You need to use Online Premium or any of the Desktop programs to enter a K-1.

To enter a K-1 go to

Federal Taxes Tab or Personal (Home & Business version)

Wages and Income

Then scroll way down to S-Corp, Partnerships and Trusts

Schedules K-1 - Click the Start or Update button

Be sure to pick the right kind of K-1. There are 3 kinds, 1041, 1065 & 1120S