IMEI vs Serial Number vs MEID: Key Differences Explained

Every mobile device has multiple identifiers — but they serve very different purposes. The IMEI is what your carrier uses to connect you to the network and block a stolen phone. The serial number is what the manufacturer uses for warranty and support. The MEID is an older American standard. Knowing which one you need — and when — prevents a lot of confusion when reporting a stolen device or buying used.

Table of Contents

1. Quick Reference: IMEI vs Serial Number vs MEID
2. What Is an IMEI?
3. What Is a Serial Number?
4. What Is a MEID?
5. Key Differences Explained
6. Which Identifier Do You Need?
7. Where to Find Each on Your Phone
8. Frequently Asked Questions

Quick Reference: IMEI vs Serial Number vs MEID

Feature	IMEI	Serial Number	MEID
Full name	International Mobile Equipment Identity	Serial Number	Mobile Equipment Identifier
Length	15 digits	Varies (8–20 chars, alphanumeric)	14 hex digits (56 bits)
Used by	Mobile carriers, national blacklist systems	Manufacturer (Apple, Samsung, etc.)	CDMA carriers (Sprint, Verizon legacy)
Purpose	Network identity, device blocking	Warranty, repair, support	Network identity on CDMA networks
Standard	GSM/UMTS/LTE/5G (global)	Manufacturer-specific	CDMA (USA, legacy)
Can be blacklisted?	Yes — across all carriers	No — manufacturer use only	Yes — on CDMA networks
Found in	Settings, *#06#, box sticker	Settings, box sticker, device back	Settings (older US phones)

What Is an IMEI?

The IMEI (International Mobile Equipment Identity) is a globally unique 15-digit number assigned to every cellular device. It is the primary identifier used by mobile networks worldwide to authenticate devices and enforce blacklists. When you insert a SIM card, your carrier checks the IMEI against its Equipment Identity Register (EIR) — if it is on the blacklist, the device is denied network access.

The IMEI is structured as: TAC (8 digits) + Serial Number (6 digits) + Check Digit (1 digit). The TAC identifies the device model and manufacturer; the serial portion identifies the specific unit. The check digit validates the number using the Luhn algorithm. Full breakdown of IMEI number structure and what each part means.

What Is a Serial Number?

The serial number is a manufacturer-assigned identifier used for internal tracking — warranty management, repair history, factory records, and support. Unlike the IMEI, it has no standard format. Apple uses alphanumeric strings like F2LWC0NMHG0R. Samsung uses strings like R58N123ABCD. Google Pixel serial numbers follow their own format.

The serial number is stored in the device’s firmware and is also printed on the retail box. It is what you use when contacting manufacturer support, registering for AppleCare, or making a warranty claim. It is not used by carriers and cannot be used to blacklist a device on a mobile network. For Wi-Fi-only devices (tablets, iPods) that have no IMEI, the serial number is the only hardware identifier.

What Is a MEID?

The MEID (Mobile Equipment Identifier) is the CDMA equivalent of the IMEI. It is a 14-digit hexadecimal number used to identify devices on CDMA networks — primarily the legacy networks of Verizon and Sprint in the United States. MEID was introduced to replace the older ESN (Electronic Serial Number) when 32-bit ESN numbers ran out.

With the shutdown of CDMA networks in the USA (Verizon ended CDMA in December 2022; Sprint’s network merged into T-Mobile), MEID is increasingly irrelevant for new devices. Modern phones sold in the USA use IMEI on LTE and 5G networks. However, you may still encounter MEID on older phones or when unlocking legacy devices.

Key Differences Explained

Scope of Use

The IMEI operates globally — a blacklisted IMEI in the UK is shared with the GSMA database and can block the device in Australia, Canada, or South Africa. The serial number only means something to the manufacturer. The MEID only means something to CDMA carrier systems, which are being phased out.

Changeability

Serial numbers are embedded at the factory and cannot be changed by the user. IMEIs are supposed to be permanent hardware identifiers, but IMEI modification is possible (and illegal in most countries). MEID is similarly locked at hardware level on CDMA devices.

Privacy Implications

The IMEI is the most sensitive of the three — it is broadcast to mobile towers every time your phone connects to a network, creating a persistent, trackable identifier. Carriers, governments, and law enforcement can use it to track device location over time. The serial number is only visible locally or when you disclose it to a service provider.

Which Identifier Do You Need?

Situation	Identifier Needed
Reporting a stolen phone to police	IMEI (both IMEI1 and IMEI2 for dual-SIM)
Asking carrier to blacklist a stolen device	IMEI
Apple warranty or AppleCare claim	Serial Number
Samsung warranty claim	Serial Number (and IMEI)
Checking blacklist status before buying used	IMEI
Unlocking an old Verizon phone	MEID (older devices) or IMEI (newer)
Insurance claim for lost phone	IMEI + Serial Number (insurers want both)
Wi-Fi-only tablet support claim	Serial Number only (no IMEI)

Where to Find Each on Your Phone

IMEI

• Dial *#06# — fastest method, works on all phones
• Settings → About phone → IMEI information (Android) or Settings → General → About → IMEI (iPhone)
• Original retail box barcode sticker
• Google account (myaccount.google.com) or Apple ID (appleid.apple.com) device list

Serial Number

• Settings → About phone → Serial Number (Android) or Settings → General → About → Serial Number (iPhone)
• Original retail box barcode sticker
• Printed on device back (some older models)
• Apple ID or Samsung account device list

MEID

• Settings → About phone (on older CDMA-capable devices, displayed alongside IMEI)
• Dial *#06# — some older US phones show MEID here instead of or alongside IMEI
• Original box sticker on older US Verizon/Sprint devices

Full guide to finding your IMEI number on any device.