Disability Retirement Benefits
If you get disability retirement benefits before you reach the minimum retirement age, you must claim the benefits as earned income when you claim the EITC.
To find your minimum retirement age,
check your retirement plan. The minimum retirement age is the earliest age you could get disability retirement benefits if you didn’t have the disability.
After you reach the minimum retirement age, your disability retirement payments do not quality as earned income.
Source:
Find out if your disability benefits qualify as earned income and if you can claim your disabled child to get the Earned Income Credit (EITC).
www.irs.gov
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I think the key here is double checking your retirement plan to find if you qualify based on your minimum requirement age. If the income is reported to you on a W-2, then it is earned income and you can contribute towards the IRA (given all of the relevant rules and limitations). If the income is reported to you on a Form 1099-R, then it is unearned and you cannot contribute towards the IRA.
Hopefully this helps clarify your situation!