@dmertz wrote:
If the Roth IRA contribution qualified you for a Retirement Savings Contributions Credit, that would explain the federal refund calculated on your amendment. Check for a Form 8880 being included in your amendment.
However, reporting the contribution shouldn't change your state tax liability, so it seems that you could have made a mistake on the state amendment, perhaps not indicating a balance due that you paid.
2 extra comments.
The retirement savers credit can pay you up to 50% of the amount you save for retirement, depending on your income. The rules are here.
https://www.irs.gov/retirement-plans/plan-participant-employee/retirement-savings-contributions-save...
Also, make sure you are NOT entering a workplace retirement plan as if it was an IRA. Qualified workplace plans (401k, 403b, etc.) are only reported on your W-2. An IRA is an individual account that you set up with your own bank or broker. If you report a workplace plan in the place for IRAs, that's wrong, and can sometimes cause other errors.
