Can I use serial number to block a stolen phone?

No. Only IMEI can be used to block a stolen phone through carriers. Serial numbers are not tracked by cellular networks, so they cannot be used to prevent a thief from using your device.

What if my phone's IMEI doesn't match the box IMEI?

A mismatched IMEI is a strong indicator of a counterfeit or cloned phone. Legitimate devices always have identical IMEI numbers on the box, in the phone's settings, and internally.

Is it illegal to change my IMEI or serial number?

Yes. Changing IMEI is illegal in most countries and constitutes device cloning. It can result in criminal charges. Serial numbers can sometimes be changed for legitimate repairs, but it's never recommended for personal use.

Should I save my IMEI and serial number?

Absolutely. Write down both your IMEI and serial number and store them securely (in email, cloud storage, or safely in writing). If your phone is stolen, your IMEI is essential for blacklisting the device with your carrier.

Difference Between IMEI and Serial Number: Key Differences & How to Use Them

Q: What is the difference between IMEI and serial number?

IMEI (International Mobile Equipment Identity) is a 15-digit number used to identify phones on cellular networks, while a serial number is a unique identifier assigned by the manufacturer for warranty and support purposes. IMEI can be used to track and block stolen phones; serial numbers cannot.

When your phone breaks down or gets stolen, you’ll often hear support agents ask for either your IMEI number or your serial number. But what’s the difference? And which one do you actually need?

In this guide, we explain the key differences between IMEI and serial numbers, how to find each one, and why both matter for your device security and warranty.

Quick Comparison: IMEI vs Serial Number

Feature	IMEI Number	Serial Number
Purpose	Identifies phone on cellular network	Identifies device for warranty & support
Format	15 digits (alphanumeric variants)	Varies by manufacturer (letters + numbers)
Used by	Carriers, government agencies	Apple, Samsung, manufacturers
For tracking	Yes — can blacklist if stolen	No — not tracked by carriers
For unlocking	Can be used by hackers	Less commonly exploited

What Is an IMEI Number?

IMEI stands for International Mobile Equipment Identity. It’s a unique 15-digit number assigned to every cellular-enabled device when it’s manufactured.

Think of IMEI as your phone’s “social security number” on cellular networks. Carriers, government agencies, and telecom authorities use it to:

Track phones on their networks
Block stolen or blacklisted devices
Verify device authenticity
Prevent fraud and cloning
Manage device switching between carriers

Learn more about IMEI structure and what each digit means.

IMEI Format

A standard IMEI looks like: 35 123456 789012 3

First 2 digits (TAC): Country of origin
Next 6 digits: Manufacturer code
Next 6 digits: Model identifier
Last digit: Check digit (Luhn algorithm)

What Is a Serial Number?

A serial number is a unique identifier assigned by the device manufacturer. Unlike IMEI, it’s not standardized across manufacturers.

Apple uses one format for iPhones. Samsung uses another for Galaxy phones. Xiaomi has its own system. Manufacturers use serial numbers to:

Verify warranty coverage and expiration
Track device repair history
Identify recalled or defective batches
Support customer service claims
Manage inventory and production

Serial Number Examples

iPhone: F2LMYQ7DJ5V (11 characters)
Samsung: R38R70GRJQL (12 characters)
Xiaomi: 0a410f4a0 (varies)

IMEI vs Serial Number: When to Use Each

Use IMEI When:

Your phone is stolen — carriers can blacklist it via IMEI
You need to understand how IMEI tracking works
You’re switching carriers or networks
Filing a police report (IMEI is official evidence)
Checking if a phone is blacklisted in your country

Use Serial Number When:

You’re claiming device warranty
Contacting manufacturer support
Checking repair history with Apple/Samsung
Returning a defective device
Verifying authenticity with the manufacturer

Can Serial Number Be Used for Tracking?

Short answer: No. Serial numbers are not tracked by carriers or cellular networks.

Unlike IMEI, which is actively monitored by telecom authorities, serial numbers exist only in manufacturer databases. A thief can’t be traced using your serial number alone — but they can be traced using your IMEI. This is why knowing your IMEI matters so much.

Where to Find Your IMEI & Serial Number

iPhone

Settings → General → About
Look for “IMEI” and “Serial Number” in the list.

Android

Settings → About Phone → Status
Or dial *#06# to see IMEI instantly (serial number not always visible).

On the Device Box

Both IMEI and serial number are printed on your phone’s original box. Check the barcode labels if you still have the packaging.

IMEI vs Serial Number: Security Implications

While both identifiers are important, they pose different security risks:

IMEI Security Risks

Hackers can clone your IMEI (illegal, but possible)
Your IMEI is visible on cellular networks
Scammers may claim your IMEI is “linked to a crime”
IMEI can be used to unlock or jailbreak devices

Serial Number Security Risks

Less commonly targeted by scammers
Harder to exploit for warranty fraud
Limited use outside manufacturer ecosystem

FAQ: IMEI vs Serial Number

Q1: Can I use serial number instead of IMEI to block a stolen phone?

No. You must provide your IMEI to carriers to blacklist a stolen phone. Serial number doesn’t work because carriers don’t track it. This is critical if your phone is stolen — always save your IMEI in a safe place.

Q2: What if the IMEI on the box doesn’t match my phone’s IMEI?

This is a red flag for a counterfeit phone. Legitimate devices always have matching IMEI numbers. The IMEI printed on the box, in settings, and internally should all be identical.

Q3: Can I change my IMEI or serial number legally?

No — changing IMEI is illegal in most countries and considered device cloning. Serial numbers technically can be changed (for repair purposes), but manufacturers take it seriously. It’s never recommended.

Q4: Which number should I write down?

Write down both. Keep your IMEI and serial number in a safe, separate place (email, cloud storage, or paper). If your phone is stolen, having your IMEI ready can get it blacklisted within hours.

Q5: Do tablets and smartwatches have IMEI numbers?

Only if they have cellular connectivity (WiFi-only devices don’t). WiFi-only iPads have serial numbers only. Cellular iPads have both IMEI and serial numbers, just like phones.

Key Takeaways

IMEI = Your phone’s ID on cellular networks (used for tracking & blocking)
Serial Number = Your phone’s ID for the manufacturer (used for warranty & support)
IMEI can be blacklisted if stolen; serial number cannot
Always save both numbers in case of theft or support needs
Mismatched IMEI = possible counterfeit device
Changing either is illegal in most jurisdictions

Next Steps

Now that you understand the difference, consider:

Save your IMEI and serial number right now
Follow our detailed guide on finding your IMEI
Check if a used phone’s IMEI is blacklisted before buying