What is Reverse Wireless Charging Technology

Did you know your phone can charge other devices without cables? Reverse wireless charging is one of those features few people know about but that can save you in unexpected situations. I use it regularly to charge my earbuds when I don’t have a charger handy, and once you try it, you’ll find uses for it. Here’s what reverse wireless charging technology is and how to take advantage of it.

Table of contents

What exactly is reverse wireless charging?

Reverse wireless charging is a technology that turns your phone into a wireless charging pad. Instead of charging your phone with a charger, your phone charges another device when placed against its back.

It works thanks to the wireless charging coil built into many flagship phones. That coil normally receives energy from a charging pad, but with reverse charging, the phone reverses the flow and sends energy to another compatible device.

It first became popular with the Huawei Mate 20 Pro in 2018, and since then Samsung, Google, Xiaomi, and OnePlus have incorporated it into their flagships. It’s not a new feature, but in 2026 it’s more efficient and faster than when it started.

How does it work technically?

Basically, the phone uses the same hardware as normal wireless charging but reverses the process. Energy goes from the phone’s battery to the coil, and from there to the receiving device.

Which devices support it?

Not all phones have reverse wireless charging. It used to be reserved for flagships, but in 2026 it’s starting to trickle down to upper-mid-range phones.

Compatible phones (2025-2026)

• Samsung: Galaxy S22 and later, Galaxy Z Fold 3 onwards, Galaxy Z Flip 3 onwards
• Google: Pixel 6 and later
• Xiaomi: Mi 11 and later (Pro/Ultra models)
• OnePlus: OnePlus 10 Pro and later
• Huawei: Mate 20 Pro and later, P30 Pro and later

Devices you can charge with it

• Earbuds: AirPods, Galaxy Buds, Pixel Buds (any case with Qi wireless charging)
• Smartwatches: Galaxy Watch, Apple Watch (with adapter), Pixel Watch
• Other phones: Any phone with Qi wireless charging
• Accessories: Some styluses and battery-equipped cases

Pro-tip: Reverse charging works with any Qi-certified device. It doesn’t need to be the same brand as your phone.

How to activate reverse wireless charging

Activating it is quick, but it varies by manufacturer.

On Samsung (One UI)

1. Go to Settings → Battery and device care → Battery
2. Look for Wireless PowerShare or Wireless charging for devices
3. Enable the feature
4. Place the device to charge face-down on the back of the phone

On Google Pixel

1. Go to Settings → Battery → Wireless charging
2. Enable Reverse wireless charging
3. Place the device on the back of the Pixel

On Xiaomi

1. Go to Settings → Battery → Wireless charging
2. Enable Reverse charging
3. Place the receiving device on the back

Usage tips

• Make sure the phone has at least 20-30% battery
• Remove the case if it’s thick or metallic, as it can interfere
• Center the receiving device over the coil (usually in the center of the back)

Warning: Reverse charging drains your phone’s battery significantly. Don’t use it as your primary charging method; it’s a solution for emergencies or occasional use.

Speed and efficiency: how long does it take?

Let’s be honest: reverse wireless charging is not fast. It’s considerably slower than a normal charger.

Speed comparison

Reverse charging power sits around 4.5W, which is similar to slow chargers from ten years ago. It’s fine for earbuds (about an hour and a half to charge Galaxy Buds), but charging another phone is quite inefficient.

How much battery does it drain from my phone?

Charging a pair of earbuds fully consumes approximately 15-20% of your phone’s battery. Charging another phone to 50% can cost you 40-60% of your own battery. It’s not sustainable for daily use, but for emergencies it works.

I mainly use it to charge my earbuds during my subway commute. By the time I get to work, the earbuds are ready and my phone has lost about 15%, which is acceptable.

Real use cases where it’s handy

Reverse wireless charging isn’t a feature you use every day, but in these situations it makes a difference:

1. Friend’s battery emergency

Your friend’s phone is at 1% and they don’t have a charger. You pass them 10-15% with reverse charging so they can make a call or order a ride.

2. Charging earbuds without a charger

You’re traveling and forgot your earbuds charger. You place them on your phone during the commute and they’re ready when you arrive.

3. Minimal packing for trips

Instead of carrying a charger for your earbuds and another for your watch, you just bring the phone charger and charge everything from it.

4. Minimalist nightstands

If you have a wireless charging pad for your phone, you charge your phone overnight and the earbuds on top of the phone at the same time.

Limitations you should know about

Not everything is perfect. Reverse wireless charging has important limitations:

• Low speed: Not practical if you’re in a hurry
• Heat: Generates more heat than normal charging, which can affect battery longevity
• Double loss: Your phone loses battery while charging another device, with efficiency losses in the process
• Positioning: You need to place the receiving device correctly; if it moves, charging stops
• Doesn’t work with thick cases: Cases with rings, built-in batteries, or metal block the transfer

The future of reverse wireless charging

Reverse wireless charging technology is evolving, and what we see in 2026 is just the beginning. There are interesting developments that could change how we use it.

Long-range wireless charging

Several companies are researching RF (radio frequency) charging, which would allow charging devices without physical contact at distances of several meters. Startups like Energous and Ossia already have working prototypes, though power is still limited (1-2W).

If this technology matures, reverse wireless charging could evolve into something much more practical: your phone charging your earbuds simply by being in the same pocket.

Higher energy efficiency

Manufacturers are improving transfer efficiency. In 2026, typical 4.5W reverse charging has around 60-70% efficiency. Next-generation chips promise 80-85% efficiency, which would mean less battery drain on your phone.

Charging multiple devices

Some prototypes show phones capable of charging two devices simultaneously. Imagine placing earbuds on the upper back and a smartwatch on the lower back. It doesn’t exist in production yet, but it’s a path manufacturers are exploring.

Pro-tip: If you use reverse charging regularly, consider a phone with a 5000 mAh or larger battery. Reverse charging drains significant battery, and a larger battery gives you more margin without running low mid-day.

Comparison with power banks: when to choose each option

Many people wonder if reverse wireless charging can replace a power bank. The short answer is no, but each has its moment.

When to use reverse charging

• You forgot the cable or charger for your earbuds
• Your friend needs 10% battery urgently
• You want to charge something without pulling out a power bank
• You’re somewhere you don’t want to carry extra things

When to use a power bank

• You need to fully charge a device (0% to 100%)
• You’ll be without outlets for hours
• You need to charge your own phone plus other devices
• Charging speed matters

Direct comparison

My advice: reverse charging for occasional emergencies, power bank for long trips. I carry both options depending on the situation.

FAQ: Frequently Asked Questions

Does reverse charging damage the phone’s battery?

Not directly, but it generates more heat than normal charging. Heat is the main enemy of lithium batteries, so excessive use can accelerate degradation. Occasional use isn’t a problem.

Can I charge an iPhone with an Android phone?

Yes, if the iPhone has wireless charging (iPhone 8 onwards). The Qi protocol is universal and doesn’t depend on the operating system.

Does reverse charging work with a case on?

It depends on the case. Thin plastic or silicone cases usually work. Thick cases, magnetic ring cases, or metal cases block the transfer. Try removing it if it doesn’t work.

How many watts does reverse wireless charging have?

Generally between 4.5W and 5W, depending on the manufacturer. Some Xiaomi phones reach 10W in reverse charging, which is noticeably faster.

Conclusion

Understanding what reverse wireless charging technology is gives you an extra tool in your tech arsenal. It’s not a daily-use feature, but in emergencies or when you forget a charger, it can save the day. If your next phone includes it, give it a try. It’s one of those features you didn’t know you needed until you use it.