This State Department page lists the steps to be taken to renew one’s US passport by mail. The page contains this text:
- Submit your Most Recent U.S. Passport
You must submit your most recent passport with your application.
Please note:
Your U.S. passport book and/or card must meet all of the requirements listed at the top of this page.
Your old passport book and/or card will be returned to you, but generally it will come in a separate mailing from your new passport.
The wording is clear that the old passport will be returned, usually in a separate mailing. I have no idea how long it will take for the old passport to be sent.
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