The new 6,000/12,000 senior deduction will be calculated on 1040 Schedule 1-A page 2 Part V Enhanced Deduction for Seniors which goes to 1040 line 13b. It is separate and in addition to the Standard Deduction or your Itemized Deductions on 1040 line 12e. Turbo Tax automatically includes it if you qualify. And your Social Security can still be taxable as before.
The maximum deduction is $6,000 for each person 65+. The phaseout is 6% of the amount by which MAGI exceeds $75,000 for single or $150,000 for married filing jointly (MFJ). The MAGI is normally the same as your AGI but with some Foreign items from Form 2555 added back in. On a joint return the phaseout is calculated separately for each person, so the 6% phases out for each spouse.
