Don’t be too surprised if AMEX’s “retention specialist” gives you a sweet incentive offer to keep your old card open and active. I got a choice of $400 or 25,000 SkyMiles to keep the account open and I have no obligation to ever use the card. Note that this is completely separate from your decision to open or not open a different Amex credit card account. My wife also accepted a generous offer to keep her card account open as well and she hasn’t charged anything to it since.