How to Charge Your Laptop Through a Portable Monitor’s USB-C Port

One of the neatest tricks of a modern portable monitor is the ability to send video and charge a laptop over a single USB-C cable. It tidies a desk, removes a charger, and keeps a laptop topped up during the day. Whether it works for you depends on a few technical details.

How USB-C Power Delivery Works

USB-C Power Delivery, or PD, allows devices to negotiate how much power flows and in which direction. A monitor with a PD input can accept power from a wall charger and pass some of it on to a connected laptop. In this setup the monitor sits between the charger and the laptop, sharing the available watts.

Does Your Monitor Support Passthrough

• Look for a USB-C port marked for power input, often with a PD rating.
• Check whether the monitor advertises power passthrough or laptop charging.
• Confirm the included charger is powerful enough for both devices.
• Note the maximum watts the monitor will forward to the laptop.

Wattage and What It Can Charge

A monitor that forwards 45W or more will keep most ultrabooks running and slowly top up their batteries. Lighter devices such as tablets and phones charge comfortably. Power-hungry gaming laptops need far more, and the monitor’s passthrough will usually only slow their drain rather than charge them fully. Match the forwarded wattage to your laptop’s needs.

Setting It Up

Plug the monitor’s power supply into the monitor’s PD input, then connect the laptop to the monitor’s video USB-C port with a cable that supports both data and power. If video appears but charging does not, the cable may carry video only, so try one rated for full USB-C functionality.

Drawbacks and Limits

Sharing power means less for each device, so under heavy load the laptop may charge slowly or hold steady rather than gain. Standards also vary by brand, so not every combination behaves the same. Test it with your own hardware and watch the charge indicator before relying on it.

Using a Multi-Port Hub

If your laptop has only one USB-C port, a small hub can split the connection so the monitor gets video while other devices get data and power. Choose a hub that supports Power Delivery passthrough, or the monitor and the laptop may both starve for watts. Check the hub’s video capability too, since some cheap models pass data and power but no picture at all. A good hub keeps the single-cable idea intact without forcing you to unplug the monitor every time you need a card reader or a second drive. A powered hub also helps when you attach several accessories at once, and matching its Power Delivery rating to your needs avoids surprises.

Knowing When Passthrough Is Not Enough

Power passthrough has a ceiling, and a demanding laptop may need more than the monitor can forward. If the battery still drains during heavy use, the monitor is only softening the loss rather than charging properly. In that case, plug the laptop’s own charger into a second port and let the monitor handle only the display. Understanding that limit stops you blaming the hardware when the wattage simply does not add up, and it keeps your expectations in line with what the technology can really deliver. Check the laptop’s reported charging rate in its settings to see what the monitor is actually providing. Keeping charging and display on separate ports, when you can, keeps both predictable.

One cable for picture and power is a genuine convenience once the wattage lines up. Browse our portable monitors and explore the portable LCD screen collection to find a screen with solid USB-C power delivery.