Are you Single or Married? Is your AGI over 75,000 (150,000 married)?
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 on 1040 line 11 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. You can not get it if you file MFS Married filing Separate.
Heres a spreadsheet I made. It matches Turbo Tax and IRS Schedule 1-A.
It is automatic based on your age. It is not part of your Standard Deduction. The new Senior Deduction is separate and in addition to the Standard Deduction or your Itemized Deductions on 1040 line 12e. The 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. Turbo Tax automatically includes it if you qualify. If you are married you have to file a Joint return.
For Online version you can preview the 1040
https://ttlc.intuit.com/community/accessing/help/how-do-i-preview-my-turbotax-online-return-before-f...
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