When you enter your 1099s and Social Security SSA-1099 into Turbo Tax you are filling out the 1040 or 1040SR. That is the tax return you send to the IRS.
The 1040SR is EXACTLY the same as the regular 1040 just bigger type so it prints on 3 pages instead of 2. They both use the same instructions and tax calculations . You automatically get the 1040SR if one spouse 65 or older.
