Anker Power Bank 20K (87W, Built-In USB-C Cable) review
By Tom Calder
A dependable mid-capacity bank that will recharge a typical phone three to four times, making it a sensible anchor for a home power-cut kit. USB-C Power Delivery means modern phones charge quickly and the bank itself refills far faster than the old micro-USB designs.
- Best for
- Keeping phones and tablets topped up through a multi-day power cut.
- Skip it if
- You need to run a laptop or want the most charges per fill, in which case step up to Anker's 25K…
as of 2 Nov 2026, 13:07 GMT · Details
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Researched, not used. We haven't used this product. This review is built from the maker's specifications, owner reports and our own sizing.
What we like
- 20,000mAh capacity charges most phones three to four times before it needs a refill
- Built-in USB-C cable plus a USB-C port and USB-A charge three devices at once, useful for a household
- Anker is a well-established brand with a solid safety and reliability record
Worth knowing
- Lower capacity than the old PowerCore 26800 it replaces, so fewer charges per fill
- 87W is shared across the ports, so charging several devices at once slows each of them
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Our review
Anker's Power Bank 20K (A1383) is a 20,000mAh bank with a built-in USB-C cable, a USB-C port and a USB-A port, 87W in total and up to 65W from either USB-C. That is enough to charge phones quickly, run a tablet and top up many laptops, and it refills at the same 65W, which matters before a forecast storm.
What Anker lists
Anker's product page for the A1383 gives 20,000mAh capacity, a built-in USB-C cable and a USB-C port that can each deliver up to 65W (up to 20V at 3.25A), and a USB-A port that tops out around 22W. The combined maximum is 87W, which is the 65W and 22W added together. It recharges through USB-C at up to about 65W. Anker lists it at 157.5 by 73.5 by 26mm and about 431g.
What 65W means at home
Most current phones charge at their fastest from this bank, and a USB-C laptop that accepts 65W, which covers many thin-and-light models, can be charged from it too. The built-in cable means there is always a lead with it, which is the thing that goes missing from a drawer. The fast recharge matters when a storm warning comes in the afternoon: with a 65W USB-C charger, it can be refilled in a fraction of the time of an old 10W or 15W bank. Anker's page does not give a refill time, and you will need your own wall charger.
How far it goes
Anker does not publish a watt-hour figure; at the usual 3.6V to 3.7V cell voltage, 20,000mAh is about 72 to 74Wh. Some energy is always lost in conversion, so in practice expect several phone charges, or roughly one charge of a small laptop, not the full number. Sharing it between several devices slows each one down because the 87W is a shared total. Our power cut preparation guide covers how many banks a household needs.
Flying and safety
At around 74Wh it is under the Civil Aviation Authority's 100Wh threshold. The CAA says power banks go in the cabin, never in checked bags, with no more than two per person, and must not be recharged on board. Keep it out of hot cars and charge it on a hard surface; our lithium battery fire safety guide explains the warning signs. Model codes vary by region, so check that a UK listing says A1383.
How it compares
On the power banks page, the Belkin BoostCharge 20K has the same rated capacity but only 15W, so it charges and refills far more slowly. The INIU Carry and UGREEN Nexode 20,000mAh banks have built-in cables and 45W. Anker's 25,000mAh 165W bank adds capacity and two cables for a laptop and phone at once, and the Anker Prime 26K gives 140W from a port for large laptops. For one phone, the Anker Nano 10,000mAh is lighter.
Our verdict
A strong middle choice: enough capacity for a few days of phone use, fast enough for a tablet or small laptop, and quick to refill. Skip it if you need to run a large laptop for long or want the most charges from one bank; Anker's 25K or Prime banks are built for that.
A researched review, built from the maker's specs, manual and UK listings; facts checked 2 Nov 2026. Sources: Anker: Power Bank 20K 87W with built-in USB-C cable (A1383); Civil Aviation Authority: Pack Right, Safe Flight; Civil Aviation Authority: changes to rules on power banks.
Who shouldn't buy this
You need to run a laptop or want the most charges per fill, in which case step up to Anker's 25K 165W laptop bank instead.
Key specs
| Capacity | 20,000 mAh |
| Max output | 87 W |
| Ports | Built-in USB-C cable, USB-C port and USB-A (87W total); recharges over USB-C |
This is a Researched review: we haven't used this product. We check every specification against at least two independent sources, re-check the UK price on a schedule where we can track it automatically, and say plainly who it isn't for. Commissions never change a rating.
If this isn’t the one
Best for Keeping phones and tablets topped up during a power cut or a long day away from the mains.
Read the review →Best for Keeping a household's phones and a tablet topped up through a power cut, in a bank small enough to carry every day.
Best for Keeping phones and a USB-C laptop going through a long power cut, with no cable to forget.
as of 2 Nov 2026, 13:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.Questions
Can the Anker Power Bank 20K charge a laptop?
Yes, if the laptop charges over USB-C at 65W or less. Anker says the built-in cable and the USB-C port each deliver up to 65W.
What does 87W mean on the Anker 20K?
It is the combined maximum across all ports: up to 65W from a USB-C plus about 22W from the USB-A. No single port gives 87W.
Can I take the Anker Power Bank 20K on a plane?
Yes, in hand luggage. At roughly 72 to 74Wh it is under the CAA's 100Wh limit. Do not put it in checked bags or recharge it in flight.
How heavy is the Anker 20K?
Anker lists about 431g and 157.5 by 73.5 by 26mm, similar to other 20,000mAh banks.
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