Deferred compensation reported in box 11 on a W-2 may or may not be subject to FICA tax withholding.
See this article:
https://www.thetaxadviser.com/issues/2014/oct/tax-clinic-01.html
https://www.irs.gov/businesses/corporations/nonqualified-deferred-compensation-audit-techniques-guid...
You should talk to the plan administrator.
**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.**
