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How fast can I charge my Samsung Galaxy S21 with an old charger?
Samsung created a whole new headache for consumers when it dropped the charger from the Galaxy S21 series. You now extra for a new charger, sift through the range of third-party options, or simply rely on an old plug you have laying around. It isn’t an easy choice to decipher—especially given the perpetually confusing state of USB-C charging standards.
Before you rush out to buy a new charger, we’ve tested a selection of older smartphone plugs and a host of newer third-party chargers to help inform your decision. Here’s everything you need to know about buying the perfect Samsung Galaxy S21 charger. Luckily, many of these picks will work for the Galaxy S22 series, too. The newer devices support up to 45W charging, so choose carefully.
Our thoughts: Samsung Galaxy S21 Ultra review
The best Samsung Galaxy S21 charger for fast charging
The entire Samsung Galaxy S21 range charges up with a maximum power rating of 25W. It achieves this using the USB Power Delivery Programmable Power Supply (USB PD PPS) standard. However, the S21 family can also obtain top speed through compatibility with the Quick Charge 4+ standard. Specifically, the phone negotiates around 2.6 amps at 9.3 volts for a total of 25W of charging power.
As such, you can’t obtain this speed when using regular USB Power Delivery, Quick Charge 3.0, or various other charging standards.
The Galaxy S21 only charges at 25W using a USB Power Delivery PSS plug. Other plugs charge too, albeit slower.
Of course, Samsung sells chargers designed to charge up its latest smartphones. The company’s 25W and 45W Travel Adapters are USB PD 3.0 PPS compliant, but you won’t need the latter unless you plan to charge up the Galaxy Note 10 Plus, S20 Ultra, or a USB PD compatible laptop or tablet.
Learn more: The best Samsung fast chargers
If you’re in the market for a futureproof 45W PPS plug, you can spend less money and achieve the same results as Samsung with the Elecjet 45W. The Elecjet 45W charger supports the required USB PD PPS charging modes, and we have tested the phone to confirm it outputs the full 25W maximum power of the Galaxy S21.
We also tested the PPS compliant Anker PowerPort III Pod 65W. It proved a bit more demanding but did eventually super fast charge the Samsung Galaxy S21 series. At $40, this charger is a competitive choice against Samsung’s 45W option but isn’t as cost-effective as the Elecjet if you’re just in the market for a phone rather than a laptop charger.
Hoping for more multi-port charging options? Check out a few of our favorites here.
Can I charge the Galaxy S21 with my old Samsung charger?
If you already own an older Samsung charger, you may not need to buy a new one to charge your Samsung Galaxy S21 smartphone quickly. Samsung’s 25W Super Fast Charging and 45W Super Fast Charging 2.0 plugs support USB PD PPS and provide the total 25W supported by the Samsung Galaxy S21 series.
Samsung shipped its 25W Super Fast Charging plug with the Samsung Galaxy Note 10, Galaxy S20, and Galaxy Note 20 series. You’ll need a pretty recent phone, but last-gen Samsung phones already have the best charger for the Galaxy S21.
Newer Samsung chargers with a USB-A port marked Adaptive Fast Charging still work with the Samsung Galaxy S21 but won’t give you quite the fastest charging speed available. These plugs revert to Samsung’s Adaptive Fast Charge standard to provide 15W to the Galaxy S21 series. You find the Adaptive plug supplied with the Galaxy S20 FE, Galaxy S10 series, and older Samsung models.
Samsung's older Adaptive Fast Charging plugs give you 15W of power, the same as newer USB PD and Quick charge accessories.
15W may not sound like a lot, but unless you spring for a USB PD PPS charger, 15W is the maximum power you’ll get from third-party plugs. We’ve tested a wide range of third-party chargers with Quick Charge and USB Power Delivery support, and the Galaxy S21 will only pull 15W from these chargers too. So you might as well save some cash and stick with an old Samsung charger.
Further reading: The best portable chargers
Charging the Samsung Galaxy S21 with old phone chargers
If you’re upgrading from another phone brand, the charging speed you’ll receive when trying to power up your new Samsung Galaxy S21 is much more hit and miss. We’ve tested chargers from Apple, Google, LG, HUAWEI, Xiaomi, and others. The table below isn’t a comprehensive list but reveals the key specs you’ll need to charge Samsung’s latest flagships quickly.
| Phone Charger | Supported Universal Standards | Samsung Galaxy S21 Charging Power |
|---|---|---|
| Phone Charger Google Pixel Charger | Supported Universal Standards USB PD (5V 3A, 9V 2A) | Samsung Galaxy S21 Charging Power 15W via USB PD 2.0 |
| Phone Charger LG 16W Fast Charge | Supported Universal Standards Quick Charge 3.0 Quick Charge 2.0 (9V) | Samsung Galaxy S21 Charging Power 15W via Quick Charge 2.0 |
| Phone Charger HUAWEI 40W Super Charge | Supported Universal Standards HUAWEI Super Charge HUAWEI Fast Charge Quick Charge 2.0 (12V) | Samsung Galaxy S21 Charging Power 9W |
| Phone Charger HUAWEI 66W Super Charge | Supported Universal Standards HUAWEI Super Charge HUAWEI Fast Charge Quick Charge 2.0 (12V) | Samsung Galaxy S21 Charging Power 15W via Quick Charge 2.0 |
| Phone Charger realme VOOC Flash Charge 3.0 | Supported Universal Standards | Samsung Galaxy S21 Charging Power 0.5W |
| Phone Charger Xiaomi 30W, 40W, and 120W adapters | Supported Universal Standards Quick Charge 3.0 Quick Charge 2.0 (12V) | Samsung Galaxy S21 Charging Power 15W via Quick Charge 2.0 |
| Phone Charger ZTE Quick Charge 3.0 | Supported Universal Standards Quick Charge 3.0 Quick Charge 2.0 (12V) | Samsung Galaxy S21 Charging Power 15W via Quick Charge 2.0 |
If you have an old phone charger that supports USB Power Delivery, Quick Charge 3.0, or Quick Charge 2.0, then it will charge up your Samsung Galaxy S21 with a maximum of 15W of power. Chargers that support proprietary fast-charging standards, such as those from HUAWEI and realme, are less likely to support these universal standards and will default back to 9W or 5W charging or might not even work at all.
Generally speaking, Chinese brands are more likely to support proprietary rather than the universal standards that the Galaxy S21 supports. More familiar Western household brands like Google and LG work reasonably well with Samsung’s latest flagships.
The same rule of thumb applies to third-party accessories from Anker, Belkin, and others. Plugs and ports that support USB Power Delivery, Qualcomm Quick Charge, and Samsung AFC offer up to 15W of power to the Samsung Galaxy S21. Standard USB ports or those that support Apple’s 2.4A standard will fall back to 9W charging or slower.
Related: The best USB-C cables you can buy
Which adapter charges the Samsung Galaxy S21 the fastest?
If you’re interested in the specific results from our Samsung Galaxy S21 charging test, check out the graph below for our complete data set.
Based on our extensive testing, the only way to achieve the Samsung Galaxy S21’s maximum 25W of charging power is to use a USB Power Delivery PPS plug. So far, we’ve only identified four chargers that power up the Samsung Galaxy S21 at full speed. These are Samsung’s 25W and 45W Super Fast Charging plugs, the Elecjet 45W Super Fast Charging adapter, and Anker’s PowerPort III Pod.
Other third-party chargers typically achieve 15W of power, which is slower but still reasonably functional. The Samsung Galaxy S21 charges at 15W over the USB Power Delivery, Quick Charge, and Samsung Adaptive Fast Charging standards. So there’s plenty of support for this speed out there from older phone plugs and third-party accessories. Just be aware that not every old phone charger or accessory will fast charge the Samsung Galaxy S21.