The return of excess must be reported on your 2017 tax return as line 7 wages. If, while while the excess was invested in the 401(k), the investment had any earnings then those earnings must also be returned. The 401(k) administrator must figure out the earnings, if any. They will report the return of contribution on a 2018 1099-R with a code P in box 7 to report on your 2017 tax return and a separate 1099-R with a code 8 in box 7 to report the earning (if any) on your 2018 tax return next year.
You do not need the 1099-R with the code P to enter that part of it now, if you know the amount and you can ignore the 1099-R with the code P when it comes in 2019.
(This does exactly the same thing as entering a 1099-R with a code P that you do not have yet)
Excess 401(k) deferrals should be reported in:
(There are several screens to click through to get to the right place)
Miscellionious Income ->
Other Income not reported on a W-2 ->
Other wages (yes) ->
House Hold employee (Continue) ->
Sick Pay (Continue) ->
Other earned income (yes) ->
Source of income (other) ->
Any other income - enter the amount of the excess deferral and an explanation.
For information see IRS Pub 525 page 10
https://www.irs.gov/pub/irs-pdf/p525.pdfNote that the IRS Pub refers to 2016 & 2017 excess reported on the 2017 tax return and does not discuss 2018 1099-R's because they have not been issued yet.
**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.**
