does ssdi count for carryforward or carryback?

Not actually carryforward or carryback.  Social Security Disability Insurance (SSDI), if paid in a lump sum in one tax year for several tax years you can use the lump sum tax method. Everything is handled in the year of the payment (2024).

You can use the SSDI lump-sum action to reduce the amount of your taxable social security, even possibly to zero.

• What is a Lump-Sum Social Security Payment?

The lump-sum election has always worked correctly in TurboTax. Have all tax returns available for each year included in the lump sum payment (shown on your SSA-1099).

This can be handled on your tax return for 2023. The Form SSA-1099 should show a total amount in box 5, and then the amount that is designated for each year in box 3. Worksheet 4 is included after Worksheet 2 is completed for each year.

Be sure to select "lump-sum" method of reporting in this situation which is all done on the tax return for the year of receipt of the benefits.  Enter the appropriate amounts for each year when you start that section of your return.   Continue to add each year for all years listed in box 3. There is no amendment required.

1. Open your TurboTax Return > Search (upper right) > type ssa1099 > Click the Jump to.... Link
2. Select Yes you received benefits > Complete your SSA-1099 > Continue > Yes I received at least one lump sum payment for 2023 or earlier > Continue
3. Type a year from your SSA-1099 > Enter the amount received for that year > Continue
4. If you received a Form SSA-1099 for an earlier year enter the box 5 amount, if not enter zero or leave it blank > Continue
5. Enter the filing status for the earlier year > Continue > Select whether you lived with a spouse in the earlier year > Continue >
6. Enter the information from the earlier year return > Continue > 
7. Add another lump sum payment (another year from box 3) if applicable or Click Done
8. Continue to follow the screens until you are back at the Income Summary page

Also enter a zero if your Social Security benefits weren't taxable or there were none in the earlier year(s) (such as for a spouse). If you are using the TurboTax CD/Download version review the Lump-Sum Social Security Worksheet in Forms.  You can also review 'Earlier Year Lump-Sum Worksheet' for each year.