How to unlock your cell phone

Published 2026-04-30 · 5 min read · 1,100 words

Most phones bought through a US carrier are carrier-locked — they only accept SIMs from that carrier. The lock exists because carriers finance phones over 24 or 36 months and need to prevent users from walking off mid-payment with a phone that works on competitors. Once the phone is paid off (or you bought it outright with cash), the lock should come off — either automatically or by request.

This guide walks through what carrier lock actually is, the FCC 2015 rules requiring carriers to unlock paid-off phones, how to actually request the unlock at each major US carrier, common eligibility gotchas, and what happens to your eSIM after the unlock.

What is carrier lock?

A carrier-locked phone has a flag in its IMEI database entry that tells the device firmware to reject SIMs from networks other than the original carrier. Practically:

Locked phone, original carrier’s SIM → works fine.
Locked phone, different carrier’s SIM → phone shows “SIM not supported” or “invalid SIM” on bootup.
Locked phone, eSIM transfer to a different carrier → the eSIM provisioning step itself rejects.

The lock is a software flag, not a hardware property. Unlocking is just the carrier flipping that flag in their IMEI database.

The FCC unlocking rules

Since 2015, US carriers have voluntarily committed (under FCC pressure) to a uniform set of unlocking rules:

Postpaid phones must be unlocked once they are paid off or the contract is fulfilled. The carrier must unlock automatically (or upon request) at no charge.
Prepaid phones must be unlocked after 12 months of service, regardless of payment status.
Active-duty military deployments qualify for unlocking on request even before payoff — valid orders required.
Carriers must respond within 2 business days to an unlock request.
Unlocking cannot cost money for current customers; the carrier may charge non-customers a fee.

These are uniform commitments, not federal law — the FCC reviews compliance via the carriers’ voluntary CTIA-coordinated framework. In practice, the big-three follow the rules; smaller MVNOs sometimes drag.

How to request unlock at each carrier

verizon">Verizon

Verizon postpaid phones are sold unlocked since 2019 with a 60-day soft lock that auto-removes. After 60 days of service, no action required — the phone is already unlocked.

Verizon prepaid (Total by Verizon, etc.) requires 60 days of activated service, then auto-unlocks.

If a Verizon phone still appears locked after the auto-unlock period: contact Verizon support via the My Verizon app or 800-922-0204 with the IMEI. Resolution is usually same-day.

t-mobile">T-Mobile

T-Mobile postpaid: phones must be (1) paid off in full, (2) on the account for at least 40 days, and (3) the line must be in good standing. Once eligible, request unlock through the T-Mobile app: Account → Lines → Device → "Mobile device unlock." Request usually completes within 2 business days; some unlock automatically once eligibility is met.

T-Mobile prepaid (Magenta prepaid, Metro): 365 days of active service required; once eligible, unlock via the same app flow or by calling 611 from the device.

AT&T

AT&T postpaid: phone must be (1) paid off, (2) line must be active for at least 60 days, (3) account must be in good standing. Submit a request through att.com/deviceunlock. Approval is typically within 2 business days; you receive a confirmation email with instructions to apply the unlock (usually inserting a non-AT&T SIM and following on-screen prompts).

Cricket Wireless (AT&T-owned): 6 months of active service required. Request via the My Cricket app or by calling 800-274-2538.

visible-mint-tello-etc">Other carriers (Boost, Visible, Mint, Tello, etc.)

Most MVNOs sell phones already unlocked — if you bought the phone from Mint, US Mobile, Visible, or Tello, no action is required. The same is true for phones purchased directly from Apple, Samsung, or Google — those are factory unlocked.

The exception: phones financed through a carrier-MVNO partnership (rare but exists) follow the parent carrier’s unlock rules.

What if I bought my phone from Apple or Best Buy?

If you bought the phone directly from the manufacturer (Apple Store, Apple online, Samsung.com, Google Store) or from a non-carrier retailer (Best Buy, Costco, Walmart) without a carrier financing plan, the phone is factory-unlocked. No unlock request needed; you can switch carriers at any time.

If you bought the phone from one of these retailers with a carrier-financing arrangement (e.g., a "Best Buy + Verizon trade-in deal"), the financing path makes the phone behave like a carrier-bought phone — locked until paid off, then unlock per the carrier’s rules above.

Verifying the unlock worked

The cleanest test: insert a SIM from a different carrier and see whether the phone activates. For physical SIMs, that means swapping; for eSIMs, that means scanning a QR code from the new carrier.

Less invasive checks:

iPhone: Settings → General → About → Carrier Lock should read “No SIM restrictions.”
Android (varies): Settings → About Phone → SIM status, or Settings → Security → SIM lock. Wording varies by manufacturer.

After unlocking: eSIM transfer and SIM swap

Once unlocked, switching to a new carrier is straightforward:

If your phone supports eSIM (iPhone XS+, Galaxy S20+, Pixel 4+): the new carrier sends an activation QR code. Scan it; the new line provisions in 5–10 minutes. See our eSIM vs physical SIM guide for details.
If you’re iPhone-to-iPhone: eSIM Quick Transfer moves the line directly from the old phone to the new one without involving the carrier.
Physical SIM: the new carrier mails a SIM kit (or sells one at retail). Swap, restart the phone.

For a full carrier-switch walkthrough including porting your number, see the switching-carriers topic hub and the interactive switch checklist.

Common gotchas

Trade-in promo lock-ins. Some "free phone with trade-in" deals require the line to stay active for 24+ months; leaving early triggers a balance owed (the value of the trade-in promo). The phone unlocks normally once paid off, but the deal recoups its discount.
Refurbished phone history. A used phone might already be unlocked from a previous owner’s carrier — or it might have an unresolved locked status. Verify before buying.
"Bad ESN/IMEI." If the previous owner reported the phone lost or stolen, or owed a balance when they switched, the IMEI is blacklisted — no carrier in the US will activate it. Always check the IMEI on Swappa or via the carrier’s IMEI checker before buying used.
International unlock vs domestic unlock. Some carriers (notably Verizon historically) ship phones with the domestic lock removed but a separate international-roaming lock that requires a separate request.

For background on the BYOD process and how unlocked phones interact with new carriers: BYOD cell phone plans guide. Glossary entries: Carrier lock, Unlocked phone, IMEI, BYOD.