Forward the mail before you leave
File the mail forward in time for it to start on your possession date.

File the mail forward before moving week, not on the morning you leave. The post office needs a start date. Use the possession date in your contract, the day you give up the house, so mail starts going to the new address when you are no longer there to collect it. Filing early also gives you a confirmation to put in the closing folder.
The post office charges a fee for a forward. Ask for the current price when you file, and keep the receipt with the confirmation. Do not guess the fee from an old move. A forward sends most letter mail. It does not, by itself, change the address on your bank, your insurer, the tax office, or the accounts you pay online. Those each need their own update.
Make a short list of the accounts that will not follow the forward. The closing company, the insurer on the house you are leaving, and anyone who drafts a payment from your account belong on it. An example: if the home insurer still has the old house as the mailing address, a bill or a notice can sit in a forwarded pile for days. Update that address when you cancel or replace the policy, and write the date you did it next to the account name.
After you arrive, check the confirmation once. If a piece of mail you expected does not show up within a couple of weeks, contact the sender directly instead of assuming the forward failed. The forward is a bridge. It is not a new address book.
What to do
- File the mail forward before moving week, with the possession date as the start.
- Ask the current fee and save the receipt with your closing papers.
- Update accounts that will not follow the forward.
- Check once after you arrive, and contact a sender directly if a piece is missing.