Originally Posted by Check Essential

I put all of it into the 401k. (Actually 90%. Gotta leave roughly 10% for social security taxes or they whack your next regular check. Ask me how I know)

There is no special header on your pay statement. It is an ordinary 401k contribution. Of course, depending on how much that contribution works out to, it can pretty much max out your 401k limit for the year.

The logic for filling the 401 early in the year is getting that money to work sooner and getting the tax advantage on the investment returns earlier.