You can refer them to IRS Pub 525 page 10
https://www.irs.gov/pub/irs-pdf/p525.pdf
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If the distribution was for a 2018 excess deferral, your Form 1099-R should have code P in box 7. If you didn't add the ex-cess deferral amount to your wages on your 2018 tax return, you must file an amended return on Form 1040-X. If you didn't receive the distribution by April 15, 2019, you must also add it to your wages on your 2019 tax return.
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If the distribution was for the income earned on an excess deferral, your Form 1099-R should have code 8 in box 7. Add the income amount to your wages on your 2019 income tax return, regardless of when the excess deferral was made. |
**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.**
