@wschwager - If you made a Traditional IRA contribution *before* April 18 and designated with the IRA trustee that it was a 2015 contribution and you failed to report it on your original filed 2015 tax return, then you do need to amend to include that contribution either as a deductible contribution which would probably increase the amount of refund, or a non-deductible contribution which would be reported on a 8606 form as part of the amended return.
If it was a Roth IRA contribution, then no action is required unless the contribution would qualify you for the savers credit (form 8880) since Roth contributions are not reported on you tax return.
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
