Review advertisers before closing a PO Box

List senders while mail still arrives

1. List every sender that uses the box, working from the mail now arriving and any recent mail you still have.
2. Mark the senders you need, such as banks, insurers, medical offices and government agencies. Give each one your new address through its own official channel.
3. For each advertiser you want to stop, check whether it offers a preference page or contact route. If it does, ask it to stop mailed advertising to the box address.
4. Arrange any address change or forwarding through the official USPS process. USPS treats forwarding as a separate service from advertiser preferences.

Which address to give

When you ask an advertiser to stop, give the box address it already uses. Ask whether that is enough to locate the advertising record before providing a new address. If the advertiser is a company you also do business with, such as a bank, you can ask it to stop marketing mail and still keep your account. Closing the account is not necessary.

Finish before the closing date

Before the box closes, save enough of each advertiser’s label and contact details to identify the request later. Record the closing date separately from any sender response. Unresolved account correspondence needs its own address update through the institution’s verified route.

Official source

• USPS: Standard Forward Mail