It is very important to be aware of the expiration date of your US passport. If it is nearing expiration, some countries will restrict your travel or not issue or renew a long stay visa. The specific policies vary with different countries, but typically it is a problem if you are under six months from expiration. To renew your passport, contact the US embassy in your retirement country. There is no need to travel back to the US to renew your passport.
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