Your proof route forks: use Apple’s official ‘No SIM restrictions’ screen for an iPhone; for other phones, use an IMEI-specific carrier confirmation—or, if no carrier ever controlled it, an IMEI-specific seller/manufacturer statement whose acceptance US Mobile has not published.
“I brought an unlocked phone from overseas and am trying to activate it on US Mobile. They are asking for official documentation explicitly stating the device is unlocked to certify the IMEI. Since unlocked phones are the norm where I bought it, my invoice and box don't explicitly say 'unlocked'. How can I prove to a US carrier that my international device is unlocked?”
Summary
Your missing word on the box does not by itself mean the phone is locked. You can build device-specific evidence now, but US Mobile’s unpublished document standard means you should get its final acceptance or refusal in writing.
Your strongest evidence depends on the phone and whether any carrier ever controlled its .
Open Settings > General > About. Apple says the iPhone is unlocked when ‘No SIM restrictions’ appears next to Carrier Lock. Make one continuous screen recording—or a matched set of screenshots—showing that status and the IMEI in About, then send it with Apple’s official support-page URL. US Mobile does not publicly promise that this evidence alone will satisfy manual certification.
Obtain written confirmation from the current or original carrier that names the exact IMEI and explicitly says the device has no SIM, network, or . US Mobile says only the carrier can confirm lock status; its Network Operators search is merely a ‘likely’ indication.
Ask the overseas seller or manufacturer to reissue the receipt or send a signed email identifying the exact IMEI and stating that it was sold factory-unlocked with no SIM/network lock. Submit that as the best available issuer record, but ask US Mobile for a written acceptance decision because its public policy does not name this as an approved substitute.
Every route still leaves a separate review; the FCC says unlocking alone does not make a phone compatible.
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Watch out for
Next steps
These steps create the strongest device-specific record available and force the review to separate unlock status from compatibility.
Before requesting certification
Record the exact model and IMEI
On iPhone, open Settings > General > About and copy the IMEI; Apple says you may need to scroll. On Android, US Mobile’s path is Settings > About phone, then scroll to the IMEI. Also save the exact activation error because US Mobile asks technical-support customers to include the device model, selected network, and error.
Requirements
Use the branch that matches your phone
Create evidence tied to that IMEI
For iPhone, make a continuous screen recording or matched screenshots of Settings > General > About showing both the IMEI and ‘No SIM restrictions’ beside Carrier Lock. For a phone bought through a carrier, obtain an email or letter from that carrier naming the IMEI and saying there is no SIM/network/carrier lock. For a factory-unlocked phone with no carrier, request the same IMEI-specific wording from the seller or manufacturer; treat it as proposed evidence, not guaranteed US Mobile approval.
Requirements
After assembling the evidence
Email one complete review request to US Mobile
Send the request to help@usmobile.com with the subject ‘Manual IMEI certification — international factory-unlocked device.’ State that the device was bought overseas, identify whether it was factory-unlocked or carrier-unlocked, and ask for a written decision on whether the enclosed proof satisfies certification. For urgent discussion, US Mobile lists 1-878-205-0088 from 9 AM–9 PM Eastern; its live chat through the US Mobile dashboard is listed as available 24/7.
Requirements
If activation is still refused
Require the decision to name the remaining issue
Ask US Mobile to state whether the refusal is (1) insufficient evidence of unlock status or (2) for that model/IMEI on the selected network. If it is the second, another unlock letter does not resolve it: the FCC says unlocking only disables blocking software and does not make a device technologically compatible.
Requirements
Legal sources
The answer comes from the FCC Cell Phone Unlocking guide, Apple Support, and US Mobile’s own compatibility, IMEI, and contact pages.
US Mobile Device Compatibility
US Mobile treats the Android network scan as an indication only and says the carrier is the confirming authority.
Checking device carrier lock status
Only your carrier can confirm the lock status on your phone, though you can also try to check on your device. Go to Settings > Connections > Mobile Networks > Network Operators and select Search. If the names of other carriers come up, your phone is likely unlocked and ready to be used anywhere.
Apple Support 109316
Apple identifies the exact on-device status that establishes an iPhone is carrier-unlocked.
About unlocking
You can find out if your iPhone is locked as follows: Open the Settings app. Tap General. Tap About. If "No SIM restrictions" appears next to Carrier Lock, your iPhone is unlocked.
FCC Cell Phone Unlocking Consumer Guide
The FCC establishes that removing a carrier lock and being compatible with another network are different questions.
Technological Compatibility
A device that works on one wireless provider's network may not be technologically compatible with another wireless provider's network. Unlocking a phone refers only to disabling software that would prevent a consumer from attempting to activate a phone designed for one wireless provider's network on another wireless provider's network. In other words, unlocking a phone designed for one network may not make the phone technologically compatible with another wireless provider's network.
US Mobile Contact Us
US Mobile publishes the email and phone channel for a documented manual review request.
Contact us directly
Call us at 1-878-205-0088 Available from 9 AM–9 PM Eastern time for urgent issues or when you prefer to talk things through. Send detailed questions or non-urgent issues to help@usmobile.com
Apple Support 108037
Apple explains where to find the iPhone IMEI that should be tied to the lock-status evidence.
Find your serial number, EID, or IMEI in Settings
The easiest place to look for these numbers is usually the Settings app. Open the Settings app, then tap General. Tap About. Look for the serial number. You might need to scroll down to find the EID, IMEI/MEID, and ICCID.
US Mobile IMEI Guide
US Mobile gives the Android settings path for retrieving the IMEI used in the review request.
Android and Google Devices
Open your phone’s Settings app → Tap About phone → Scroll to view your IMEI.
US Mobile Device Compatibility
US Mobile describes unlocked-device compatibility as likely, not guaranteed.
Device compatibility
Most devices are compatible with our networks (especially devices made since 2013). Any unlocked phone or device that has a SIM card slot or is eSIM capable will most likely work with our services.
These are the official FCC, Apple, and US Mobile rules and instructions as published on the cited dates; rules and carrier procedures can change.
This is general information about official processes, not legal advice, and SettleKit is not a law firm.
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