To connect a portable monitor to a laptop, plug in a USB-C cable if both devices support video over USB-C, or use an HDMI cable plus a separate power source if they don’t. Then open your display settings and choose to extend your screen. Most setups take less than two minutes.
The tricky part is knowing which cable and port you’ve got, so let’s sort that out first.
Check what ports your laptop has
Look at the sides of your laptop. A USB-C port might have a small DisplayPort or lightning-bolt (Thunderbolt) symbol next to it. That symbol hints that it can send video. Some USB-C ports only handle data and charging, and a screen plugged into one of those will stay black.
If you don’t see a symbol, check your laptop’s manual or spec sheet for “DisplayPort over USB-C” or “video output.” While you’re at it, look for an HDMI port, since that’s the other common option.
The easy way: a single USB-C cable
This is the easiest route. One cable carries both the picture and the power, so there’s nothing else to plug in.
- Connect the USB-C cable between the monitor and your laptop’s video-capable port.
- Wait a few seconds for the screen to light up.
- If nothing appears, try the other USB-C port or a different cable.
A word on cables: a cheap charge-only cable won’t carry video. Use the one that came with the monitor, or a cable rated for video and data.
The older way: HDMI plus power
Older laptops often lack USB-C video, but they usually have HDMI. Here’s how that setup works.
- Plug the HDMI cable into the laptop and the monitor (a mini or micro HDMI end is common on portable screens).
- Power the monitor with its USB cable, connected to a wall charger or a spare USB port.
- Switch the monitor’s input to HDMI if it doesn’t do so automatically.
It’s a bit more clutter, but it works with almost any laptop.
How to handle power
When a portable monitor draws power from your laptop, it eats into the battery. That’s fine at a desk with the charger plugged in, but it can shorten a long day away from an outlet.
Many monitors have a second USB-C port for power pass-through. If yours does, plug your laptop charger into the monitor, and it may power both the monitor and the laptop. Check the manual first, since not every model passes power through. Otherwise, a small wall adapter or power bank can run the monitor on its own.
Set up the display in your settings
Once it’s connected, you’ll want to decide how the screens work together.
- Windows: press the Windows key and P, then choose “Extend.” For finer control, open Settings, then Display.
- macOS: open System Settings, go to Displays, and drag the screens into the arrangement that matches your desk.
Here you can also change resolution, rotate the screen to portrait, and pick which one is your main display. If text looks tiny or huge, adjust the scaling.
Troubleshooting a screen that won’t show up
- Try a different cable and a different port.
- Make sure the monitor has power and is on the right input.
- Restart the laptop with the monitor connected.
- Update your graphics driver.
- Don’t force a connector that won’t fit; check that it’s the right type.
Pick the right display mode
After you plug in, you’ve got a choice about how the two screens behave. It’s worth taking a moment to pick the one that fits your task.
- Extend: the monitor acts as extra desktop space. This is the most useful mode for everyday work.
- Duplicate (mirror): both screens show the same thing. It’s handy for presentations, when you want to face the audience but still see your slides.
- Second screen only: your laptop’s own screen turns off. That’s useful if you want to close the lid and use the laptop like a small desktop computer.
Use a stand and good placement
Where you put the monitor matters more than you’d think. For comfort, try to keep the top of both screens at similar heights, and put the one you look at most directly in front of you. A stand or fold-out cover helps with that. Raising the laptop on a small stand can also line the screens up and keep your neck happier.
Connecting to other devices
You don’t have to stop at laptops. Many portable monitors also work with phones that support video output over USB-C, and with game consoles or small computers through HDMI. The steps are the same: connect, power, and select the correct input. Some phones need an adapter, so check what yours supports.
A short checklist before you leave home
- Pack the right cable, and a spare if you have one.
- Bring a power source if your laptop battery is small.
- Test the setup once at home so you aren’t fixing settings in a cafe.
- Carry the monitor in a padded sleeve, since screens scratch easily.
Frequently asked questions
Can I connect a portable monitor without USB-C?
Yes. Use an HDMI cable for video and a regular USB port or wall charger for power.
Why is my portable monitor black?
The most common cause is a USB-C port without video support or a charge-only cable. Try another port or cable first.
Can I use two portable monitors at once?
It depends on your laptop’s ports and graphics. Many laptops support two external screens, but check your laptop’s specs.
The bottom line
Connecting a portable monitor to a laptop is simple once you know your ports. For help picking one, see our guide to the best portable monitors for laptop work, the general best portable monitors list, or the best space saving portable monitors for laptops if your desk is small. Still not sure it’s for you? Read whether portable monitors are worth it.