Choose capacity around the time you will be away from a socket: a smaller pack keeps a day bag lighter, while a 20,000mAh-class model gives more reserve for several devices or longer trips. Check the output of the specific USB-C port, your cable and device compatibility, and for flights use the watt-hour label and the operating airline’s current rules.
Choose enough reserve for maps, tickets, photos and messaging without carrying a heavy bag. Compare the exact weight, dimensions and independently tested charge count, not mAh alone. Which? notes that smaller power banks it tested tended to weigh about 115g and typically charged an average smartphone once.
A 10,000mAh-class pack is a general-purpose route for phones and occasional tablet charging. Move to a 20,000mAh-class model when longer reserve or charging more than one device matters more than bag weight, and check that at least one output suits your device.
Keep a clearly labelled, undamaged power bank in the cabin rather than checked luggage. UK Civil Aviation Authority guidance requires power banks in the cabin, while individual airlines may add rules on quantity, storage and use.
Start with the amount of reserve you genuinely need, then check carrying comfort, the port you will use and any flight requirements.
| Priority | What to check | Your needs |
|---|---|---|
| Usable energy | Use mAh as a size guide, then compare independently tested real-device charge counts where available. For flights, read the watt-hour marking printed on the pack. | I need enough power for the time away from a socket, rather than relying on an advertised capacity figure alone. |
| Weight and size | Compare the exact model’s weight and dimensions. Higher capacity can provide more reserve but usually adds carrying bulk. | I want a charger that will stay in my pocket or day bag for the whole trip, not one I leave behind because it is too bulky. |
| Charging speed | Check the wattage on the exact USB-C or USB-A port, the number of ports and how output is shared when several devices are connected. Check recharge input if you have little time before leaving. | My phone, tablet or compatible laptop needs a charging mode that the bank, cable and device can all support. |
| Safety and traceability | Buy an identifiable model from a reputable retailer, retain the model number and follow the maker’s charging instructions. Check recall notices for older or second-hand units. | I want to be able to identify the product if a safety recall affects it and to recharge it with sensible precautions. |
| Flying rules | Check the Wh label, keep the pack in cabin baggage and read the policy of the airline operating your flight. Carrier rules can be stricter than general guidance. | I need a pack that I can carry correctly when flying and store where my airline requires. |
Advertised capacity does not directly equal the number of real device charges. Which? tests charge counts with real devices because output can vary materially between products.
Choose a capacity class for the trip first, then compare independently tested charge-count results where possible. When flying, use the printed Wh rating rather than estimating from mAh alone.
A power bank’s output rating is its maximum offer. Actual speed also depends on the receiving device, the port in use and the cable, while multi-port charging can change the power available to each device.
Match the stated USB-C or USB-A port specification to your phone, tablet or laptop, and use a cable rated for the charging mode you need.
The UK Civil Aviation Authority says power banks must stay in the cabin because lithium batteries can overheat. Ryanair and easyJet also publish carrier-specific handling requirements.
Keep the bank in cabin baggage, protect it from damage and short circuits, and reread the policy for the airline operating your flight shortly before travel.
Incorrectly packed lithium batteries can delay a flight if baggage has to be off-loaded.
Specific Anker models A1681, A1689 and A1647 were recalled in the UK in 2025 after a fire-risk finding. Electrical Safety First also advises buying from reputable retailers and registering a power bank where possible.
Keep the model number and proof of purchase, register the product if offered, and check GOV.UK recall notices before using an older or second-hand unit.
Its UK-listed range includes compact 10,000mAh travel models, magnetic options and higher-capacity power banks. The A1259 Nano is a 10,000mAh wired model with an integrated USB-C cable.
Its UK-listed range includes high-output USB-C power banks for phones, tablets and compatible laptops. The Nexode 20,000mAh model lists 72Wh capacity, three output ports and up to 100W USB-C output.
Belkin’s UK portable charger range includes integrated-cable models for travellers who prefer to pack fewer separate cables. The BPB006 has attached USB-C and Lightning cables and can charge two devices.
Its UK and EU store range includes compact 10,000mAh models and higher-output variants. The B61 Carry Slim lists 10,000mAh capacity with USB-C input and output.
These Joybuy options focus on medium-capacity and higher-reserve power banks for keeping phones, tablets and compatible USB-C devices charged on day trips, travel and longer periods away from a socket.
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A higher-power compact option for compatible phones, tablets or laptops on a day out, with built-in USB-C and Lightning cables to reduce loose accessories.
Stated 10,000mAh capacity, USB-C and USB-A ports, and up to 45W charging for one compatible device through USB-C or the built-in USB-C cable. When charging several devices, total output is stated as 15W. Check the Wh label before flying; the supplied safety guidance also says to keep it at least 15cm from pacemakers and medical implants.
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A slim 10,000mAh option for a small bag or pocket when a compatible magnetic phone connection and a wired USB-C fallback are useful.
Stated weight is 182g and thickness is 0.5 inches. It lists up to 22.5W wired output and magnetic wireless charging up to 15W; iPhone wireless charging is specified at 7.5W. Magnetic attachment needs a MagSafe-compatible phone or suitable magnetic case.
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A wired 10,000mAh travel option for phone and tablet charging, with an integrated USB-C cable to make packing simpler.
It lists up to 33W output, 30W self-recharging, an additional USB-C port and a USB-A port for up to three connected devices. The stated 22.5W condition applies to compatible Xiaomi smartphones using the integrated cable; other devices may charge differently.
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A phone-first travel charger for people who want a built-in USB-C cable and the option to connect a second device through USB-A.
Stated capacity is 10,000mAh, with 22.5W maximum output, 20W input and a charging-status display. The built-in USB-C cable is described as usable for both charging compatible devices and recharging the power bank; actual charging speed depends on device, port and cable compatibility.
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A larger-reserve route for camping, longer journeys or repeated phone and tablet charging when minimal carry weight is less important.
It lists 20,000mAh capacity, an integrated two-way USB-C cable and up to 22.5W output. The stated optimal performance condition is for the integrated cable and compatible Xiaomi smartphones; other cables need 3A support and suitable fast-charging protocols. Check the Wh label and airline policy before flying.
Yes, subject to the carrier’s rules. UK Civil Aviation Authority guidance says power banks must stay in the cabin and never go in checked luggage; batteries from 100Wh to 160Wh require airline approval, while those over 160Wh are prohibited in passenger baggage. Check the label on the actual power bank and your operating carrier before departure.
The UK Civil Aviation Authority says passengers can take two power banks per person. Ryanair also currently states a maximum of two per passenger, but placement and other conditions can vary, so check the policy for the airline operating your flight.
No. Check the watt-hour label rather than mAh alone. For example, UGREEN lists its 20,000mAh Nexode 100W model as 72Wh, below the CAA’s 100Wh threshold, but airline rules on quantity, storage and use still apply.
The listed output is only the maximum the power bank can offer; the device, port and cable must support the same charging mode. Check the output of the specific port you will use: INIU, for example, lists USB-C on its B61 at up to 20W and USB-A at up to 22.5W.
Charge it uncovered in a ventilated place, protect it from damage and liquids, and keep it away from conductive items such as coins or keys. Electrical Safety First advises against charging power banks overnight or while out of the house; stop using a unit that is damaged, overheating or swelling and check current recall notices.