SATA Enterprise Hard Drives: Which Ones Qualify and What They Cost per TB

Enterprise grade 3.5 SATA hard drive: the rule behind these tables

We have not found a maker document that defines the word enterprise for hard drives, so the tables here use our own rule. A row counts if its maker line or part-number family is an enterprise one: Seagate Exos, WD Ultrastar, WD Gold, Toshiba MG or HGST Ultrastar. It must also be listed as 3.5-inch with a SATA interface. The rule describes a product line. It is not a quality rating, and it promises nothing about the particular unit a seller ships.

An enterprise listing with no interface or form factor recorded cannot match, and one with no capacity recorded has no £/TB figure, whichever maker it comes from. 2.5-inch enterprise drives are outside this page altogether.

SATA enterprise hard drive prices: new offers, lowest £/TB first

The new table holds 46 rows at this refresh. Seagate Exos 26TB Internal Hard Drive sits at the top on £23.04/TB, or £599.00 for the whole drive. The smallest outlay anywhere in the table is £178.15, which can be a different drive. Recording prints a technology only where we hold a document.

Refurbished enterprise SATA hard drives: the used rows

Used offers are ranked apart, because a used drive and a new one at the same capacity are not the same purchase. This table has 33 rows, and the lowest is Seagate Exos 26TB Internal Hard Drive (used) at £20.49/TB. The table labels a row New or Used and has no refurbished label, so anyone looking for refurbished enterprise hard drives in SATA starts here and checks the Amazon.co.uk listing for how the seller describes the drive.

Two parts of the Consumer Rights Act 2015 matter for a consumer buying a used drive from a trader. The short-term right to reject faulty goods runs for 30 days. Satisfactory quality is assessed with the price in mind where relevant, so what you paid is part of the test. Neither is a maker's warranty. The wider used market is the subject of refurbished enterprise hard drives.

4TB, 8TB, 16TB and 22TB SATA enterprise hard drives

These four tables mix new and used in one list, so read the Condition column before comparing two rows. The part numbers come from Seagate's Exos data sheet. They show what to look for in the Part number column and say nothing about which parts are in stock.

4 TB: 4 rows, lowest £37.50/TB. Seagate's standard 512e/4Kn SATA model at this size is ST4000NM024B.

8 TB: 7 rows, lowest £50.00/TB. Seagate's matching part is ST8000NM017B. Its sheet rates this 2 TB to 10 TB family at 2,000,000 hours MTBF and 0.44% AFR, with a 5-year limited warranty.

16 TB: 5 rows, lowest £23.46/TB. Seagate's SATA parts here are ST16000NM002H (standard) and ST16000NM001H (SED), which belong to the same table as its 12 TB, 20 TB and 24 TB models.

22 TB: 4 rows, lowest £26.42/TB. We have not found a document that names a 22 TB SATA enterprise part number. The part number printed in the row is the only identifier this page can offer, so check it with the maker before you buy.

Toshiba MG Series at 8TB, 16TB and 20TB: SATA enterprise hard drives

Toshiba's MG Series page says the series comes with SATA and SAS interfaces, in capacities from 1 TB to 24 TB. It rates each member at 550 TB/year and gives the series a 5-year limited warranty. Those statements cover the whole series, so neither separates the three sizes below. The page offers both interfaces across the series, so these tables filter on the interface recorded in each listing.

Each table is narrow by construction: one maker line, one capacity, one interface, one form factor. At this refresh they hold 1, 1 and 1 rows. Because each filter is this narrow, read each table as the state of its own rows and not as a market. The whole line is ranked on Toshiba MG Series.

What Seagate and WD state for their SATA models

WD marks its MTBF and failure-rate figures as projected values, and the two power tests use different loads, so those rows are not like for like. Seagate's rating assumes 8,760 power-on hours per year. All of it is what the makers state, not what we measured. We hold no WD Gold specification, so WD Gold rows get no figures here.

Two different 24 TB Exos part families are easy to confuse. The table above covers ST24000NM002H (standard) and ST24000NM001H (SED), and Seagate's press release of 18 October 2023 describes the 24TB Exos X24 as CMR-based. The same sheet lists a separate SATA 6 Gb/s line at 32 TB, 30 TB, 28 TB and 24 TB, also CMR, with the part numbers ST32000NM004K, ST30000NM004K, ST28000NM003K and ST24000NM001K. ST24000NM001H and ST24000NM001K differ by one final letter, so match the whole string.

Field failure data for enterprise drives: one fleet, not a ranking

Backblaze's Q2 2026 table reports failures from its own fleet, and it lists a model only with a drive count above 100 and more than 10,000 drive days. It has no interface column. Two enterprise models in its table show why the raw counts belong beside the rate:

• Toshiba MG08ACA16TA (16 TB): 39,932 drives, 100 failures over 3,614,263 drive days, an annualised failure rate of 1.01%.
• Seagate ST12000NM0008 (12 TB): 18,521 drives, 145 failures over 1,671,057 drive days, an annualised failure rate of 3.17%.

These rates come from different populations and different ages, 33.7 months for the Toshiba and 73.7 months for the Seagate, so they do not rank the two models against each other, or the drive a buyer will receive. A row in our tables with the same part number is the same model, not the same unit, and it says nothing about how a used drive has been treated. Hence no failure rate appears as a column in any table here.

Where a SATA enterprise hard drive fits

Seagate's support note sets the rule: SATA drives may be plugged into SAS controllers, and SAS drives cannot be plugged into SATA controllers. That makes SATA the interface to buy for a desktop or a SATA-only server, and it still works where a SAS controller is fitted. If the controller question is open, SAS vs SATA sets the two tables against each other and SAS hard drives ranks the other side.

We name no server or NAS model on this page, because we hold no document tying these drives to a particular machine. Before buying, check the interface in the row against your own system's documentation and any drive list its maker publishes.