email account

At one time Cox offered the option of continuing your email service for $9.99 a month. Online only.  It was wonderful. You could monitor the people who had forgotten to change or delete your email address.  It was expensive but it was worth it not to lose any communications.  Cox discontinued the service.  

Your best bet is to start using a new email address at least 30 days before you cancel your Cox service. Phone and email everyone about your new address.  Don't use the "old" Cox for anything. Watch daily to see who "forgot" to change your address. Phone them again.  If you start doing this early enuf, you can catch 95% of all the people and companies that use your Cox address to communicate with you.  There will always be a bank or a website or a friend who will keep the old address and send you something you wish you had gotten.   The only way to be absolutely sure is to keep the Cox for 3-6 months and watch as the number of incoming emails drops to zero.