If I over-contributed to my 2017 401K, can it be carried over to 2018 return?

[pk]

you have to the administrator to see if they can effect that

[2018t3]

I am not self employed. My employer put some $ in my 401 and I mistaken added $6,500 in March of 2018 for the tax year 2017. Did not realize there was an over contribution until after tax time.