I am on K3 and waiting for my EAD. I am wondering if I should be applying for my social security # now or should I wait for the EAD to arrive.

You will have to wait till you have your EAD in hand to apply for a SSN

thanks. looks like your process was really quick. good luck with your new job.

another quick question, did you get your drivers license switched over before getting the SSN?

Most states require a SSN to obtain a US drivers license. Check with your local DMV.