Every UK hard drive & SSD, ranked by real £/TB — live Amazon.co.uk pricesEvery UK hard drive & SSD, ranked by real £/TB — live Amazon.co.uk pricesFour-bay NAS units on Amazon.co.uk, ranked by price. Four drives in RAID 5 give you three drives' worth of space and survive one failure — the sweet spot for a media server or a small office. See also 2-bay NAS.
| Product | Bays | Price | £/bay | Drives | Rating | Fill it | |
|---|---|---|---|---|---|---|---|
 | QNAP TS-431K 4 Bay Desktop NAS Enclosure | 4 | £444.50 | £111.13 | Diskless | ★ 4.4 (205) | 4 × 8TB £1,199.96 in drives |
 | Asustor AS5304T 4 Bay NAS | 4 | £601.35 | £150.34 | Diskless | ★ 4.4 (489) | 4 × 8TB £1,199.96 in drives |
 | QNAP TS-451+-8G 4 Bay Desktop High-performance NAS Enclosure | 4 | £799.95 | £199.99 | Diskless | ★ 4.1 (85) | 4 × 8TB £1,199.96 in drives |
£/bay is the price divided by the number of drive bays, so a £300 four-bay NAS (£75/bay) is better value for growth than a £200 two-bay (£100/bay). Fill it adds the cost of filling every bay with today's cheapest drive of the chosen size from our NAS drive rankings — change the size above the table. Units sold with drives are listed after the diskless ones, because their price already includes storage.
Beyond bays, the things that matter most are the CPU (Intel/AMD models handle Plex transcoding and Docker far better than ARM/Realtek), RAM, and network speed: a 2.5GbE port is roughly two and a half times faster than gigabit for big file copies. Not sure whether you need a NAS at all? Read NAS vs DAS, then choose drives with our NAS drive guide.
A NAS (network-attached storage) is a small always-on computer full of drives that sits on your home or office network. Every device on the network can store files on it, stream from it and back up to it, and most run apps such as Plex, photo backup and Docker.
Bays decide how much storage a NAS can hold and how it can protect it. Dividing the price by the number of bays lets you compare a 2-bay box with a 4- or 8-bay one fairly. CPU, RAM and network speed then decide how fast it is.
Most are sold diskless, so you choose the drives. Some, such as Buffalo LinkStation or Synology BeeStation, include them; those show the capacity in the Drives column and are listed after the diskless units.
Use CMR drives made for 24/7 use: Seagate IronWolf, WD Red Plus or Pro, Toshiba N300, or enterprise drives such as Exos at larger sizes. Our NAS drive hub ranks them all by price per terabyte.