TerabytePricesStorage deals · Amazon UK

From £16.75/TB·2,145 products·Updated 3 Jul 2026

best external hard drive for backup

Best external hard drive for backup UK 2026

Last updated 3 July 2026Live Amazon UK prices
External hard drive connected for backup with files, photos, and documents syncing securely to the cloud
The best backup drive is at least 1.5× your data size, with the lowest price per terabyte you can find. Desktop drives usually win on value; portable drives win on convenience.

Best value external drives right now

#ProductCapacityPricePer TB
★WD 16TB My Book external hard drive, Desktop HDD with Password Protection, USB 3.0, SuperSpeed USB, software for device management, backup, hardware encryption, works with PC and Mac, Black16TB£268.02£16.75/TB
2Seagate Expansion Desktop 20TB, External Hard Drive, USB 3.0, Data Rescue Services (STKP20000400)20TB£359.99£18.00/TB
3Seagate Expansion Desktop 20TB, External Hard Drive, USB 3.0, Data Rescue Services (STKP20000400)20TB£359.99£18.00/TB
4Seagate Expansion Desktop 20TB, External Hard Drive, USB 3.0, Data Rescue Services (STKP20000400)20TB£394.24£19.71/TB
5Seagate Expansion Desktop 16TB, External Hard Drive, USB 3.0, Data Rescue Services (STKP16000400)16TB£317.99£19.87/TB

View all 204 external hard drives →

How much backup storage do you need?

Backing upRecommended sizeBest format
Laptop1TB – 2TBPortable USB
Desktop PC2TB – 4TBDesktop or portable
Mac Time Machine2× Mac storageDesktop (always on)
Photo / video library4TB – 8TBDesktop
Whole household8TB+Desktop or NAS

Portable vs desktop

Portable (2.5-inch)

  • Bus-powered, easy off-site storage
  • Up to ~5TB
  • Higher £/TB than desktop

From £23.91/TB

Desktop (3.5-inch)

  • Best £/TB, up to 20TB
  • Faster 7200 RPM options
  • Needs mains power

From £16.75/TB

The 3-2-1 backup rule

Keep 3 copies of important data, on 2 types of media, with 1 copy off-site (cloud or another location). One external drive at home is not enough on its own.

Frequently asked questions

What is the best external hard drive for backup?

For portable backup, 2–5TB USB drives work well. For full PC or Time Machine backups, desktop 4–8TB drives offer better £/TB.

How much storage do I need for a backup drive?

Buy at least 1.5–2× the data you are protecting so multiple backup versions fit.

What is the 3-2-1 backup rule?

3 copies of data, on 2 media types, with 1 copy off-site (cloud or another location).

Portable vs desktop external drive?

Portable drives are bus-powered and easy to store off-site. Desktop drives offer better £/TB and higher capacities.

Compare external hard drives

All portable and desktop drives sorted by £/TB.

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