How to Find Any Laptop Serial Number

Every laptop has a unique serial number that identifies the exact device, not just the model line or configuration. You may need it for warranty claims, insurance records, repairs, theft reports, company asset management, driver downloads, or resale documentation. Because the serial number is tied to manufacturer records, it is worth finding it carefully and recording it in a secure place.

Why the Laptop Serial Number Matters

A laptop serial number is a manufacturer-assigned identifier used to distinguish one physical machine from every other unit produced. Two laptops may have the same model name, processor, memory, and color, but they will not have the same serial number. Manufacturers use this number to confirm warranty status, repair history, original configuration, eligibility for recalls, and sometimes ownership transfer requirements.

It is important not to confuse the serial number with nearby labels such as model number, product ID, SKU, part number, asset tag, or Windows product key. These may be useful, but they are not always unique to your device. When support staff asks for a serial number, they usually need the exact manufacturer serial, service tag, or equivalent identifier.

1. Check the Physical Laptop First

The most direct method is to inspect the exterior of the laptop. Turn the device off, unplug the charger, and place it on a clean, soft surface. On many laptops, the serial number is printed on a sticker or etched directly into the bottom cover. It may be labeled as Serial Number, S/N, SN, Service Tag, or Serial.

Common places to check include:

• Underside of the laptop: The most common location for Dell, HP, Lenovo, ASUS, Acer, and many other brands.
• Inside the battery compartment: Older laptops with removable batteries may have the serial number under the battery.
• Back edge or hinge area: Some ultrabooks place small text near the rear ventilation area.
• Original manufacturer label: Look for labels containing barcodes or QR codes; the serial number may be printed beside them.

If the printed text is faded, use strong indirect lighting and take a close-up photo with your phone. Zooming in on the image is often easier than reading the label directly.

2. Look at the Box, Receipt, or Warranty Documents

If the laptop is not available or the label has worn off, check the original packaging. Manufacturers often print the serial number on the outside of the retail box near the barcode. Business laptops may also include the serial number on shipping labels, packing slips, leasing paperwork, or inventory documents.

Purchase receipts and invoices do not always include serial numbers, but many corporate and education suppliers list them for asset tracking. If you bought the laptop online, sign in to your account with the retailer or manufacturer and review order details. Warranty confirmation emails may also include the serial number or a link to the registration page where it was recorded.

3. Find the Serial Number on Windows

On most Windows laptops, the serial number can be retrieved from system firmware using Command Prompt or PowerShell. This is especially useful when the external label is missing.

To use Command Prompt:

1. Click Start.
2. Type cmd.
3. Open Command Prompt.
4. Enter the following command:

wmic bios get serialnumber

Windows should display the serial number beneath the SerialNumber heading. On newer Windows systems, PowerShell is often preferred. Open Windows Terminal or PowerShell and run:

Get-CimInstance Win32_BIOS | Select-Object SerialNumber

If the result says To be filled by O.E.M., Default string, or appears blank, the manufacturer may not have written the serial number correctly into firmware. In that case, use the physical label, BIOS screen, box, or manufacturer support page instead.

4. Find the Serial Number on a MacBook

Apple makes the process relatively straightforward. On most MacBooks, click the Apple menu in the top-left corner and select About This Mac. The serial number appears in the overview window. In newer versions of macOS, you can also go to System Settings, choose General, then select About.

You can also find a MacBook serial number printed on the underside of the device, on the original packaging, or in your Apple account if the Mac is associated with your Apple ID. If the Mac will not turn on, the physical engraving or original box may be the best option.

5. Find the Serial Number on Linux

Linux users can usually retrieve the serial number from the system’s DMI information. Open a terminal and run:

sudo dmidecode -s system-serial-number

You may be asked for your administrator password. If the command is unavailable, install the dmidecode package using your distribution’s package manager. For example, on Debian or Ubuntu-based systems, use:

sudo apt install dmidecode

Some systems may return a placeholder value if the manufacturer did not store the serial correctly. If that happens, check the BIOS or physical label.

6. Find the Serial Number on a Chromebook

For a Chromebook, the serial number is usually printed on the bottom cover or the original box. If the Chromebook is working, you can also find device details by opening the status area, going to Settings, and checking the About ChromeOS section. Managed school or business Chromebooks may also have a separate asset tag, but the manufacturer serial number remains the key identifier for hardware service.

7. Check BIOS or UEFI Firmware

If the operating system cannot start, the BIOS or UEFI firmware screen may still show the serial number. Restart the laptop and press the manufacturer’s setup key during startup. Common keys include F2, F10, F12, Esc, or Del, depending on the brand.

Once inside, look for sections such as System Information, Main, About, or Device Information. The serial number may appear alongside BIOS version, product name, motherboard details, and service tag. Do not change firmware settings unless you know what they do; simply read and record the serial number, then exit without saving changes.

8. Use Manufacturer Support Apps or Websites

Many laptop makers provide official support utilities that detect device information automatically. Examples include Lenovo Vantage, HP Support Assistant, Dell SupportAssist, MyASUS, Acer Care Center, and Samsung Settings. These tools often show warranty status, model name, and serial number in one place.

You can also sign in to the manufacturer’s support website if you previously registered the device. Some brands allow warranty lookup by account, order number, or service tag. If you contact support, be prepared to provide proof of purchase, especially if the serial number is needed for ownership verification.

What If the Serial Number Is Missing or Unreadable?

If no method produces a valid serial number, gather all related identifiers: model number, product number, service tag, motherboard serial, purchase invoice, order number, and photos of the laptop. Contact the manufacturer directly and explain that the label is damaged or the firmware value is missing. For business devices, your IT department may have the serial number in an asset management system or mobile device management platform.

Be cautious with second-hand laptops that have removed labels, altered firmware information, or missing ownership documents. That does not automatically prove a problem, but it can make warranty service, resale, or insurance claims harder.

Record It Securely

Once you find the serial number, store it somewhere reliable: a password manager note, encrypted document, warranty folder, or company asset database. Avoid posting it publicly in forums or marketplace listings. While a serial number is not usually as sensitive as a password, it can be misused in fraudulent warranty claims or social engineering attempts.

A good practice is to record the serial number, model name, purchase date, retailer, and warranty expiration date together. This small step can save time later if your laptop is lost, stolen, damaged, or due for service.