What is the last date of making contribution to 401k for 2017. Where can i find the info on IRS website?

[Micky]

I read in several forums that I can make the contribution after Dec 31st and mark it for 2017. How can this be achieved?

[LisaBr · Accepted solution]

Contributions for 401(k) have two deadlines:

Contributions deadline for Employees elective deferrals is last paycheck or 12/31/2017

Total Contribution deadline (Employer non-elective deferrals) is until 4/15/2018 (plus extensions)

https://www.irs.gov/retirement-plans/plan-participant-employee/retirement-topics-401k-and-profit-sha...

[Micky]

Thanks, this is good, but how to di make Non Elective Deferrals? My employer / payroll processor s claiming they cannot do it.