The fastest way depends on your computer's manufacturer and age

Resetting a BIOS password is not the same as resetting a Windows or Mac password. You cannot do it from your operating system. Instead, you need to either clear the CMOS battery on your motherboard, use a manufacturer reset tool, or contact the computer maker for a backdoor code — and which one works depends on whether your machine is a laptop or desktop, and how old it is.

Desktops are usually easier because you can open the case and physically remove the CMOS battery, which holds the BIOS settings in memory. Laptops often require a service tag or serial number to get a reset code from the manufacturer. Some newer machines have a BIOS reset button on the motherboard itself.

Key Takeaways

  • Removing the CMOS battery from a desktop motherboard for 10 to 15 minutes clears the BIOS password on most machines built before 2015.
  • Laptops usually require you to contact the manufacturer with your service tag or serial number to receive a one-time reset code.
  • Some newer desktops and laptops have a physical CMOS reset button or jumper on the motherboard that does the same job without removing the battery.
  • Opening your computer case will void the warranty on some machines, so check your documentation or contact support before you start.
  • If you own the computer but cannot prove it, manufacturers may refuse to issue a reset code for security reasons.

Clearing the CMOS battery on a desktop

The CMOS battery is a small coin-shaped battery on the motherboard that stores BIOS settings, including the password. Removing it for a few minutes resets everything to factory defaults, including the password. This works on most desktops made in the last 20 years.

First, shut down the computer completely and unplug the power cable from the wall. Press the power button once to discharge any remaining power. Open the case — on most towers, this means removing one or two screws on the back and sliding the side panel off. Locate the CMOS battery, which looks like a large watch battery, usually silver and about the size of a dime. Note which direction it faces (the + side usually points up). Gently pry it out with a plastic spoon or a non-metal tool, and wait 10 to 15 minutes. Put the battery back in the same direction it came out, close the case, plug in the power cable, and turn the computer on. The BIOS password should now be cleared.

If you cannot find the battery or are uncomfortable opening the case, look for a jumper labeled CLR_CMOS, CLEAR CMOS, or PSWD on the motherboard. Moving this jumper to a different set of pins for a few seconds does the same job as removing the battery. Check your motherboard manual if you are unsure which pins to move.

Getting a reset code from the laptop manufacturer

Laptop manufacturers do not want you opening the case because it voids the warranty and can damage delicate components. Instead, they issue one-time reset codes if you can prove you own the machine. You will need your service tag or serial number, which is usually printed on a sticker on the bottom of the laptop or inside the battery compartment.

Contact the manufacturer's support line — Dell, HP, Lenovo, Apple, and others all have different processes. Tell them you are locked out of the BIOS and have the service tag ready. They will ask you to verify ownership, usually by providing the original receipt, proof of purchase, or the last four digits of the credit card used to buy it. If you can verify ownership, they will give you a reset code that works one time. Enter this code at the BIOS password prompt, and the password will clear.

If you cannot prove ownership — for example, if you bought the laptop used or inherited it — most manufacturers will refuse to issue a code. In this case, your only option is to contact a local computer repair shop, which may have tools to bypass the password or clear the CMOS on some laptop models. This will cost money and may not work on newer machines with encrypted BIOS settings.

Using a physical reset button or jumper

Some newer desktops and a few high-end laptops have a physical CMOS reset button or jumper on the motherboard. This is faster than removing the battery and does not require you to wait. Look for a button labeled CMOS, CLR, or RESET, or a jumper labeled CLR_CMOS or PSWD.

For a button, straightforward press and hold it for three to five seconds while the computer is powered off and unplugged. For a jumper, move the plastic cap from one set of pins to a different set (usually the middle position) for a few seconds, then move it back. Check your motherboard manual or the manufacturer's website for the exact location and procedure on your specific model.

What happens after you reset the BIOS password

When you clear the CMOS, all BIOS settings return to factory defaults. This means your boot order may change, any custom settings you made will be lost, and your hard drive may no longer be recognized in the correct order. You will need to go back into the BIOS and reconfigure these settings if necessary.

If your computer was set to boot from a specific drive or in a specific order, you may need to change that again. If you had disabled certain hardware or set custom fan speeds, those changes will be gone. Most of the time, the defaults work fine and you will not notice any difference.

Avoiding a locked BIOS in the future

If you set a BIOS password yourself, write it down and store it somewhere safe — a password manager, a locked drawer, or a trusted family member. If you forget it, you will have to go through the reset process, which takes time and may void your warranty.

If you are selling or giving away a computer, clear the BIOS password before you hand it over. This prevents the new owner from being locked out. If you buy a used computer and it has a BIOS password, ask the seller for the password before you complete the purchase. If they cannot provide it, you will have to reset it yourself using one of the methods above.

When to contact a professional

If you are uncomfortable opening your computer case, or if your laptop manufacturer refuses to issue a reset code, a local computer repair shop can help. They have tools and experience with different motherboards and laptop models. Expect to pay between $50 and $150 for this service, depending on your location and the complexity of your machine.

Some shops can also help if your BIOS is encrypted or if you have a newer machine with security features that prevent straightforward password resets. If your computer is still under warranty, contact the manufacturer first — they may reset the password for you at no cost if you can prove ownership.

Frequently Asked Questions

Will resetting the BIOS password erase my files?

No. Clearing the CMOS only resets BIOS settings, not the data on your hard drive. Your files, programs, and operating system will still be there. You will just need to reconfigure some BIOS settings like boot order.

Can I reset the BIOS password without opening the case?

On desktops, not usually — you need to remove the CMOS battery or move a jumper, both of which require opening the case. On laptops, you must contact the manufacturer for a reset code. Some newer machines have a BIOS reset button you can press from the outside, but this is rare.

What if I do not have the service tag for my laptop?

The service tag is usually printed on a sticker on the bottom of the laptop or inside the battery compartment. If you cannot find it, the manufacturer's support team can sometimes look it up using your serial number or other identifying information. Have your receipt or proof of purchase ready.

Does resetting the BIOS password void my warranty?

Opening the case on a desktop may void the warranty depending on the manufacturer. Laptops are more sensitive — opening them almost always voids the warranty. Contact the manufacturer or check your warranty paperwork before you open the case. Using a manufacturer-issued reset code does not void the warranty.

Can I reset the BIOS password if I do not own the computer?

Manufacturers will not issue a reset code without proof of ownership for security reasons. If you own the computer but cannot prove it, you will need to use the CMOS battery or jumper method on a desktop, or take it to a repair shop. On a laptop, a repair shop may be your only option.