Connect via Bluetooth in three steps

The Logitech MX Master 3S pairs to your computer through Bluetooth, the same wireless standard you use for headphones or keyboards. Turn on the mouse, hold the pairing button on the bottom for three seconds until the LED blinks, then go to your computer's Bluetooth settings and select "MX Master 3S" from the list. The connection completes in seconds and stays active until you manually unpair it or the mouse runs out of battery.

If your computer doesn't find the mouse, make sure Bluetooth is turned on in your system settings. On Windows, open Settings > Bluetooth & Devices > Bluetooth and look for the mouse in the list. On Mac, go to System Settings > Bluetooth and do the same. The mouse will appear as "MX Master 3S" — if you see multiple entries, you may have paired it before; select the one with the strongest signal indicator.

Once paired, the mouse remembers your computer. The next time you turn it on near that computer, it reconnects automatically without pressing the pairing button again. You only need to repeat the pairing process if you want to connect the mouse to a different device or if the pairing somehow fails.

Key Takeaways

  • Press and hold the pairing button on the bottom of the mouse for three seconds until the LED blinks, then select it from your computer's Bluetooth settings.
  • Windows users find Bluetooth settings under Settings > Bluetooth & Devices > Bluetooth; Mac users go to System Settings > Bluetooth.
  • The mouse remembers your computer after the first pairing and reconnects automatically each time you turn it on nearby.
  • If the mouse does not appear in Bluetooth settings, check that Bluetooth is turned on and that you are holding the pairing button long enough for the LED to blink.
  • You can pair the MX Master 3S to multiple computers, but it only connects to one at a time.

What to do if the mouse doesn't appear in Bluetooth settings

The most common reason the mouse doesn't show up is that Bluetooth is turned off on your computer. Check your system tray (bottom right on Windows, top right on Mac) for a Bluetooth icon and click it to turn Bluetooth on. Wait a few seconds, then try the pairing process again. If you still don't see the mouse, restart your computer's Bluetooth by turning it off and back on.

If the LED on the mouse doesn't blink when you hold the pairing button, the battery may be dead. Plug the mouse into a USB-C charger for at least 30 minutes, then try pairing again. A fully charged MX Master 3S should pair within three seconds of pressing the button.

On Windows, if you see "MX Master 3S" in the Bluetooth list but it won't connect, right-click it and select "Remove device," then try pairing from scratch. On Mac, click the X next to the mouse name in Bluetooth settings to forget it, then pair again. This clears out any corrupted pairing data that might be blocking the connection.

Switching the mouse between multiple computers

The MX Master 3S can pair to up to three computers at once, but it only connects to one device at a time. After you pair it to your first computer, you can pair it to a second or third computer using the same process: hold the pairing button for three seconds and select the mouse from Bluetooth settings. Each computer will remember the pairing.

To switch between computers, press the pairing button on the bottom of the mouse for one second (not three) to cycle through your paired devices. The LED will blink once for the first computer, twice for the second, and three times for the third. The mouse disconnects from the current computer and connects to the one you selected. This switch happens in about two seconds.

If you want to remove a computer from the pairing list, go to that computer's Bluetooth settings and select "Remove device" or "Forget" next to the MX Master 3S. This frees up one of the three pairing slots if you want to add a new computer later.

Using the Logitech Options app for extra features

The mouse works without any software — Bluetooth alone is enough to move the cursor and click. However, Logitech offers a free app called Logitech Options+ that lets you customize button assignments, adjust scroll speed, and set up gesture controls. read it from Logitech's website for Windows or Mac.

After you install Options+, open it and the app will detect your MX Master 3S automatically. You can then reassign the side buttons to do things like open a specific program, switch between apps, or trigger a screenshot. The app also shows your mouse battery level and lets you set up different button layouts for different programs — for example, one layout for Photoshop and another for your web browser.

Options+ is optional. If you never install it, the mouse still pairs and works normally. The side buttons will have their default functions, and you won't be able to customize them. The app is useful only if you want to change how the mouse behaves.

Troubleshooting connection drops and lag

If the mouse connects but then disconnects randomly, the battery may be low. Plug it in to charge and check the battery level in Logitech Options+ or in your computer's Bluetooth settings. A low battery can cause the connection to drop even if the mouse still turns on.

Interference from other wireless devices can also cause lag or disconnections. Wi-Fi routers, cordless phones, and microwave ovens all use the 2.4 GHz frequency that Bluetooth uses. If you notice lag when the microwave is running or when you move closer to your Wi-Fi router, try moving the mouse farther from those devices or moving them farther from your computer.

If the mouse lags only on one computer but works fine on another, the problem is usually that computer's Bluetooth hardware or drivers. On Windows, go to Device Manager, find "Bluetooth" in the list, right-click it, and select "Update driver." On Mac, this is less common, but you can try restarting your computer and re-pairing the mouse. If lag persists on one computer, that computer's Bluetooth may need repair or replacement.

Pairing the mouse to a computer without Bluetooth

If your computer doesn't have Bluetooth built in, you can add it with a USB Bluetooth adapter. Plug the adapter into any USB port on your computer, wait for the drivers to install (usually automatic on Windows and Mac), then pair the mouse the same way you would with built-in Bluetooth. The adapter acts as a Bluetooth receiver for your computer.

Logitech also sells a USB receiver called the Unifying Receiver that works with the MX Master 3S, though it is not required. The Unifying Receiver lets you pair multiple Logitech devices to one USB port, which can be useful if you have a keyboard and mouse from Logitech. To use it, plug the receiver into a USB port and hold the pairing button on the mouse for three seconds; the mouse will pair to the receiver instead of Bluetooth.

Bluetooth is the simpler option if your computer has it. A USB adapter or Unifying Receiver is only necessary if your computer lacks Bluetooth or if you prefer a wired connection method.

Frequently Asked Questions

How long does the battery last on the MX Master 3S?

Logitech rates the battery at up to 70 days of typical use on a single charge. Heavy users may see 30 to 40 days; light users may see longer. The mouse will notify you when the battery is low, and you can charge it with any USB-C cable while continuing to use it.

Can I use the mouse while it's charging?

Yes. The MX Master 3S works while plugged in, so you can keep using it while the battery charges. You don't have to wait for a full charge to disconnect the cable.

What if I pair the mouse to a new computer and forget to unpair it from the old one?

The mouse will still work on both computers, but it will only connect to one at a time. When you turn it on, it will connect to whichever computer it was last paired with. Press the pairing button for one second to switch between computers, or go to the old computer's Bluetooth settings and select "Remove device" to free up a pairing slot.

Does the MX Master 3S work with tablets or phones?

Yes, it pairs to any device with Bluetooth, including iPad, iPhone, and Android tablets. Use the same pairing process: hold the button for three seconds and select the mouse from Bluetooth settings. The mouse works as a cursor on tablets and phones, though some apps may not support mouse input.

Why does my mouse keep disconnecting when I move it far from my computer?

Bluetooth has a typical range of 30 feet in open space, but walls, metal objects, and other obstacles reduce that range. If your mouse disconnects when you move it to another room, you are likely outside the Bluetooth range. Move closer to your computer or remove obstacles between the mouse and your computer's Bluetooth receiver.