For a federal refund you can put a change of address (form 8822), see the following FAQ
How do I change my address with the IRS?
https://ttlc.intuit.com/replies/3301581
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From the instructions of the 8822 form:
Foreign Address
Follow the country’s practice for entering the postal code. Please do not abbreviate the
country.
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If you have a state refund, you can check your states website for their change of address form.