With all the stupid and unjustified uses of SSN, it's sort of funny to see this as the one people are objecting to. Working out Social Security contributions for your paycheck is pretty much the most reasonable use for that number I can think of.
Re:Why I Don't Sign Non-Competes
by chrisabrams on Wednesday March 21, 2018 @04:23PM
(#16642010)
I was speaking generally, not specifically employers. I was asked for my SSN to get a mailbox once...
Depending on work relationship (e.g. contract), they may not be doing this anyway. But there are some things they need it for.