Open App →
Home›AT&T Check

AT&T IMEI Check

Enter your IMEI to instantly check if your device is locked to AT&T, blacklisted, or eligible for unlocking.

No signup · 3-second result

What Is an AT&T Carrier Lock?

Why AT&T phones reject other SIM cards

📡

What Is SIM Lock

AT&T locks financed and prepaid devices to its network until unlock requirements are met. A locked AT&T phone will only accept AT&T SIM cards. Inserting a T-Mobile, Verizon, or other carrier SIM will display "SIM Not Supported" or "Invalid SIM."

⛔

Blacklist Risk

AT&T devices with unpaid balances, reported lost, or associated with fraudulent accounts may be placed on the GSMA blacklist. A blacklisted phone will not work on any US carrier network. An IMEI check reveals this risk before you buy or switch.

🔍

What IMEICheck Shows

Whether the original carrier is AT&T, SIM Lock status (locked/unlocked), blacklist status, device model, warranty info, and original carrier details — all in one report.

AT&T Official Unlock Policy (2026)

Find out if your device qualifies for free unlocking

💳

Postpaid

AT&T postpaid devices must be paid in full and active on the network for at least 60 days. The account must be in good standing with no past-due balance. Installment plans must be fully paid off before unlocking.

📱

Prepaid

AT&T prepaid devices must be active for 6 months (180 days) on the AT&T network. The device must not be reported lost or stolen, and the account must have no outstanding balance.

🔗

Unlock Portal

Once eligible, visit the AT&T Device Unlock portal to submit your request. You will need your IMEI number and AT&T account credentials. Unlock requests are typically processed within 24–48 hours.

Note: The above is a summary of AT&T's public unlock policy. Refer to AT&T's official website for authoritative information. IMEICheck is not affiliated with AT&T.

How to Check AT&T Lock Status

Step-by-step guide to verify your device

Step 1: Find Your IMEI

Dial *#06# on your AT&T phone. The 15-digit IMEI number will display on screen. Alternatively, go to Settings → About Phone → Status → IMEI, or check the original box barcode label. For iPhones, the IMEI is also printed on the SIM tray.

Step 2: Enter IMEI in the Form

Type or paste your 15-digit IMEI into the search form above. Double-check the digits — a typo will return incorrect results. The check runs instantly and does not require an account or payment for basic status.

Step 3: Review the Report

The IMEICheck report shows SIM Lock status, original carrier (AT&T or other), blacklist status, device model, and production info. If the device shows "Locked to AT&T," you need to meet the 60-day postpaid or 6-month prepaid requirement before requesting an unlock.

Step 4: Request Unlock if Eligible

If the device is eligible (active 60+ days postpaid or 6+ months prepaid on AT&T, paid in full, no outstanding balance), visit the AT&T Device Unlock portal at att.com/deviceunlock/ to submit an unlock request. The device should unlock within 24–48 hours.

How to Unlock an AT&T Phone

Four ways to get your device unlocked

🌐

Online Portal

Visit att.com/deviceunlock and submit an unlock request. You will need your IMEI number, AT&T account credentials, and the device must meet eligibility requirements. This is the fastest method, with most requests processed within 24–48 hours.

📞

Customer Service

Call AT&T customer service at 1-800-331-0500. A representative will verify your account and device eligibility, then submit the unlock request on your behalf. Have your IMEI number and account PIN ready when calling.

🏪

In-Store Visit

Visit an AT&T retail store with a valid ID and your device. A store representative can verify eligibility and submit the unlock request. This is a good option if you prefer face-to-face assistance or have account access issues.

📱

Auto-Unlock

AT&T automatically unlocks eligible devices that have been fully paid off and meet the active day requirement. If your device qualifies, you may receive a text message confirming the auto-unlock. Insert a non-AT&T SIM to verify the unlock was applied.

AT&T Blacklist Check

Protect yourself from blacklisted devices

An AT&T phone is blacklisted when its IMEI is added to the GSMA blacklist database, which is shared across all major US carriers including Verizon, T-Mobile, and Sprint. Once blacklisted, the device cannot connect to any cellular network in the United States. Common reasons for blacklisting include: the device was reported lost or stolen, the account has an unpaid balance or was closed with an outstanding equipment installment plan, or the device was obtained through fraudulent activity.

Running an IMEI check before purchasing a used AT&T phone is critical. If the IMEICheck report shows "Blacklisted," do not buy the device — even if the seller claims it can be "cleaned" or "unlocked." Removing a blacklist entry requires the original account holder to resolve the issue with AT&T directly, which may involve paying off the outstanding balance or providing proof of ownership. Third-party blacklist removal services are unreliable and often fraudulent.

If your own AT&T device is blacklisted, contact AT&T customer service at 1-800-331-0500 to verify the reason. If it is an unpaid balance, settle the bill and request blacklist removal. If the device was reported stolen in error, provide proof of purchase to have the blacklist entry removed. The removal process typically takes 24–72 hours after the issue is resolved.

AT&T vs Other US Carriers

Compare AT&T with Verizon, T-Mobile, and Sprint

⏱️

Unlock Speed

AT&T requires 60 days for postpaid and 6 months for prepaid — slower than Verizon's 60-day auto-unlock but comparable to T-Mobile's 40-day postpaid requirement. Sprint (now T-Mobile) required 50 days. AT&T is mid-range for unlock speed among major carriers.

📶

Network Technology

AT&T uses GSM technology, same as T-Mobile. Verizon and Sprint historically used CDMA. Modern 4G LTE and 5G networks have largely converged, but older AT&T phones may not support all Verizon or Sprint bands. Always verify band compatibility when switching carriers.

💰

Plan Pricing

AT&T's postpaid plans are comparable to Verizon in price, generally slightly more expensive than T-Mobile's Magenta plans. AT&T offers unlimited data plans, family discounts, and bundle deals with DirecTV and AT&T Fiber internet. Prepaid brand Cricket Wireless offers budget-friendly options.

🌐

Coverage Area

AT&T has the second-largest 4G LTE coverage in the US, after Verizon. 5G coverage is expanding rapidly with both low-band and mmWave deployments. AT&T's coverage is strongest in the eastern and southern US, while Verizon leads in rural areas.

📱

Device Selection

AT&T carries the latest iPhone, Samsung Galaxy, Google Pixel, and other Android devices. Device payment plans spread the cost over 30 months — longer than T-Mobile (24 months) but similar to Verizon. AT&T also offers trade-in promotions for existing customers.

🔄

Carrier Switching

Once unlocked, AT&T devices work seamlessly on T-Mobile and other GSM carriers. Switching to Verizon requires checking band compatibility. The Number Transfer Port process typically takes 24–48 hours. Do not cancel your AT&T service until the port is complete to avoid losing your number.

FAQ

How do I check if my AT&T phone is unlocked?

Enter your 15-digit IMEI number in the form above. IMEICheck will instantly show whether your device is locked to AT&T or unlocked, along with blacklist status and original carrier information. You can also check via the AT&T Device Unlock portal at att.com/deviceunlock/.

How long does AT&T take to unlock a phone?

Once you submit an unlock request through the AT&T Device Unlock portal, AT&T typically processes it within 24–48 hours. Postpaid devices must be paid in full and active for 60 days. Prepaid devices must be active for 6 months (180 days).

What does it mean if my AT&T phone is blacklisted?

A blacklisted AT&T phone has been reported lost, stolen, or has an unpaid balance. The IMEI is added to the GSMA blacklist shared across all major US carriers, meaning the phone cannot connect to any carrier network. Contact AT&T customer service to verify and resolve the issue.

Can I use an unlocked AT&T phone on T-Mobile or Verizon?

Yes. Once unlocked, AT&T devices support T-Mobile and other GSM carriers. For Verizon, compatibility depends on the device model and band support. Always verify band compatibility with your target carrier before switching.

Can I check if a used AT&T phone is unlocked before buying?

Yes. Ask the seller for the 15-digit IMEI (dial *#06# on the device) and run it through IMEICheck. The report shows SIM Lock status, original carrier, and blacklist status in seconds — protecting you from buying a locked or blacklisted device. Always verify before purchasing.

AT&T IMEI Check Tips

💡

Check Before Buying

Always run an IMEI check before purchasing a used AT&T phone. Verify SIM Lock status, blacklist, and unlock eligibility to avoid buying a device you cannot use.

📋

Keep Your IMEI Handy

Save your IMEI number after checking. You will need it for unlock requests, warranty claims, and insurance filings. Dial *#06# anytime to retrieve it.

⚠️

Beware of Scams

Third-party unlock services that charge fees are often unnecessary — AT&T provides free unlocks for eligible devices. Use the official AT&T Device Unlock portal instead.

Check Your AT&T Device Now

Free SIM Lock · Blacklist · Unlock Eligibility Check

Check Now →

Note: IMEICheck is an independent service and is not affiliated with AT&T. All trademark rights belong to their respective owners. Unlock policy information is summarized from AT&T's public website for educational purposes.