Thanks. This is a moving, unpredictable target. Ten or twenty years ago, some of my airline accounts required middle initial, and it was usually optional. That said, I think things may be tightening up. My passport and REALID drivers license have always included my full middle name. Within the last few years, I've updated both my NCL account (easy, over the phone) and Southwest account (required a written request through their website). Chase credit cards used to only allow initial, but are now allowing full middle name on the application/account (but the card still just displays initials....for now).