If you have an account with that bank, insurance etc., login into the account and unsubscribe from unwanted communications.If you receive unsolicited mailers like credit card offers, insurance offers etc, carefully read the mailer that should have a clause for how to unsubscribe or opt-out. You will have to call that number or submit a request online for not to send such offers. This unsubscribe request will be valid for 5 years.