If you're trying to terminate a relationship with a contractor or other business, a contract termination letter is professional. Some important things to include when writing a termination letter would be to add the date and time termination will take affect. With whom the termination is with and a few reasons for terminating your relationship. Do not use personal insults and/or aggravating
. wording when writing the letter. It is also a good idea to follow-up with the termination letter to make sure the other party has received it and to make sure they understand it.