Transferring your 401k allows you the option of never having to take physical custody of your funds as they move between your 401k and your new IRA account. This does not get reported to the IRS, so if you transfer it to a broker or firm you aren’t happy with, don’t worry, you still have the ability to move it again within the same calendar year without restriction. This method will allow you to move your securities over (more on this below).
With a Rollover, however, you’ll be getting a check from your 401k sponsor after you request liquidation. You will then have the responsibility to deposit this amount into a rollover IRA account within a a certain amount of time (discussed below). You can only do one rollover a year, so be prepared with a destination you can live with for a little while.