Question: Q: If I buy an iPhone in the U.S will it work with a mexican SIM?

Hey alvaro135,

If I understand correctly, you want to buy an unlocked iPhone and use it in another country. Make sure you use a supported SIM card from a supported carrier.

"You might see this message on your computer or on your iPhone: "The SIM card inserted in this iPhone does not appear to be supported. Only compatible SIM cards from a supported carrier may be used to activate iPhone. Please insert the SIM card that came with your iPhone or visit a supported carrier store."

If you see this message, use these steps:

1. Restore your iPhone to factory settings.
2. Contact your carrier to make sure that they applied the unlock in their system.
3. Restore your iPhone from a backup."

How to unlock your iPhone for use with a different carrier

"Mexico

AT&T1

• FaceTime over Cellular
• LTE
• Personal Hotspot

Movistar1

• FaceTime over Cellular
• LTE
• Personal Hotspot2

Oui

• FaceTime over Cellular
• LTE
• Personal Hotspot

Telcel1

• FaceTime over Cellular
• LTE
• Personal Hotspot2
• Unlocking2
• Visual Voicemail
• VoLTE"

Wireless carrier support and features for iPhone in Latin America and the Caribbean

Please don't hesitate to let us know if the steps resolved your issue or if you need additional assistance.

Thank you for using Apple Support Communities. Have a good one.

If you buy the unlocked "sim free" version yes. It will work.

Do note that warranty will only be valid in the U.S. so for any warranty service the iPhone will need to be returned to the U.S. App,le does not take international shipments for service.