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WD vs Seagate: Reliability & Price Comparison

Western Digital and Seagate are the only two major HDD manufacturers left. Both make excellent drives, but their product lines, warranty policies, and pricing strategies differ. This page puts their drives side by side so you can compare real prices and make an informed choice instead of relying on brand loyalty.

The reliability question

Backblaze publishes quarterly drive failure data from their datacenter fleet. As of 2025–2026, both WD and Seagate enterprise drives show annual failure rates between 0.5–2.5% depending on model and age. No brand has a decisive reliability edge. Individual model selection matters more than the logo on the label.

Quick Verdict

Who this is for
NAS builders, server admins, and storage shoppers trying to decide between WD and Seagate product lines.
What usually wins
Compare specific models, not brands. WD Red Plus vs Seagate IronWolf, WD Ultrastar vs Seagate Exos. Pick whichever is cheaper at your target capacity. Both are reliable when used within their rated workloads.
Prioritise
Price per TB for equivalent-tier drives. Then warranty length and workload rating for your specific use case.

Prices updated daily from Amazon.com. All links go directly to the retailer. Details.

Bottom line: the lowest price-per-TB pick on this page right now is the Water Panther WP Expanse 18TB 7200 RPM 512e SATA Gen3 3.5-inch HDD | ECC PLP CMR | Enterprise Data Center SAN Hard Disk Drive - WESA5SLC0180D, 18 TB used, at $328.99 ($18.28/TB) on Amazon.com. Check the current price.

Western Digital Drives, Best Prices

WD hard drives across all product lines ranked by price per TB.

$26.00/TB New

HGST Ultrastar He 3.5-inch 6000GB 64MB Cache 7200RPM SATA Ultra 512n Helium Platform Enterprise HDD HUS726060ALA640

6 TB Internal 3.5" SATA
$156.00 Amazon US· 2h 5m
$26.67/TB New

HGST Ultrastar He8 Helium 6TB 3.5-Inch 7200RPM SATA ULTRA 512e SE 128MB Cache Internal Bare or OEM Hard Drive - HUH728060ALE604 / 0F23669

6 TB Internal 3.5" SATA
$160.00 Amazon US· 57m
$29.52/TB New

HGST HGST Ultrastar He8 8TB 3.5" 128MB 7200RPM SAS Ultra 512E ISE 128MB Cache 12Gb/s Internal Hard Drive - HUH728080AL5200 / 0F23268 128 MB Cache 3.5-Inch Internal Bare or OEM Drives 0F23268

8 TB Internal 3.5"

SAS interface. Needs a host bus adapter, it will not plug into a normal motherboard.

$236.14 Amazon US· 44m
$31.25/TB New

Western Digital Re 4TB SAS Datacenter Capacity Hard Drive 3.5 inch 7200 RPM 32MB Cache | WD4001FYYG |

4 TB Internal 3.5"

SAS interface. Needs a host bus adapter, it will not plug into a normal motherboard.

$125.00 Amazon US· 58m
$31.75/TB New

HGST Deskstar 3.5-Inch 4TB 7200 RPM SATA III 6Gbps 64MB Cache Internal Hard Drive (0F14681) (HDS724040ALE640)

4 TB Internal 3.5" SATA
$127.00 Amazon US· 58m
$32.50/TB New

Western Digital HUS726T4TALA6L4 4TB Ultrastar DC HC310 SATA HDD - 7200 RPM Class, SATA 6 Gb/s, 256MB Cache, 3.5"

4 TB Internal 3.5" SATA
$129.99 Amazon US· 2h 30m
$33.33/TB New

Western Digital 18TB WD Red Pro NAS Internal Hard Drive HDD - 7200 RPM, SATA 6 Gb/s, CMR, 512 MB Cache, 3.5" - WD181KFGX

18 TB Internal 3.5" SATA
$599.99 Amazon US· 36m
$33.33/TB New

WD 6TB 3.5" AE Datacenter Archive SATA III 64 MB Cache Enterprise Hard Drive (WD6001F4PZ)

6 TB Internal 3.5" SATA
$200.00 Amazon US· 1h 51m

Seagate Drives, Best Prices

Seagate hard drives across all product lines ranked by price per TB.

$27.92/TB New

Seagate Exos X24 24TB internal server Hard drive ST24000NM000C 3.5" HDD SATA3 512MB 7200RPM

24 TB Internal 3.5" SATA
$669.99 Amazon US· 2h 27m
$28.09/TB New

Seagate Technology ST16000NM007H 16TB Exos X24 HDD 3.5 SAS 7200 ISE Bare Hard Drive

16 TB

SAS interface. Needs a host bus adapter, it will not plug into a normal motherboard.

$449.49 Amazon US· 2h 49m
$28.16/TB New

Seagate ST6000NM0024 6TB 7.2K SATA 3.5" HDD

6 TB Internal 3.5" SATA
$168.95 Amazon US· 13m
$30.42/TB New

Seagate ST12000VN0008 12 TB Ironwolf Hard Drive SATA 7.2K 3.5 256 MB

12 TB Internal 3.5" SATA
$364.99 Amazon US· 1h 58m
$31.25/TB New

Seagate 8TB BarraCuda Internal Hard Drive | SATA 6 Gb/s (ST8000DM004)

8 TB Internal 3.5" SATA
$249.99 Amazon US· 4m
$31.25/TB New

Seagate Barracuda 16TB Internal Hard Drive, 7200 U/Min, 512MB Cache, SATA 6Gb/s, 3.5" (ST16000DM001)

16 TB Internal 3.5" SATA
$499.99 Amazon US· 3h 50m
$32.50/TB New

Seagate Exos 7E8 ST4000NM0115 4TB 7.2K RPM SATA 6Gb/s 512e 128MB 3.5inch Hard Drive (Renewed)

4 TB Internal 3.5" SATA
$129.99 Amazon US· 13m
$32.50/TB New

Seagate 8TB 3.5" Expansion Desktop USB 3.0 External Hard Drive

8 TB External 3.5" USB
$259.99 Amazon US· 12m

Refurbished Enterprise, WD Ultrastar vs Seagate Exos

Recertified datacenter pulls from both brands, the cheapest high-capacity drives available.

$16.66/TB Used

Toshiba MG07SCA 12 TB Hard Drive - 3.5 Internal - SAS [12Gb/s SAS]

12 TB Internal 3.5"

SAS interface. Needs a host bus adapter, it will not plug into a normal motherboard.

$199.94 Amazon US· 3h 4m
$18.28/TB Used

Water Panther WP Expanse 18TB 7200 RPM 512e SATA Gen3 3.5-inch HDD | ECC PLP CMR | Enterprise Data Center SAN Hard Disk Drive - WESA5SLC0180D

18 TB Internal 3.5" SATA
$328.99 Amazon US· 3h 23m
$20.38/TB Used

WD Ultrastar DC HC590 0F65672 - 26 TB

26 TB Internal 3.5" SATA
$529.99 Amazon US· 2h 26m
$21.13/TB Used

HPE 819201-B21 8TB 12G SAS 7.2K LFF 512E SC MDL Hard Disk Drive

8 TB Internal 3.5"

SAS interface. Needs a host bus adapter, it will not plug into a normal motherboard.

$169.00 Amazon US· 3h 15m
$21.36/TB Used

Toshiba 14TB SATA 512e 256MB Cache 7200RPM 3.5" SATA 6.0Gb/s Enterprise Hard Drive - MG07ACA14TE (Renewed)

14 TB Internal 3.5" SATA
$299.00 Amazon US· 3h 30m
$21.43/TB Used

Avolusion PRO-T5 Series USB 3.0 External Hard Drive for WindowsOS Desktop PC/Laptop - 2 Year Warranty (14TB White) (Renewed)

14 TB External 3.5" USB
$299.99 Amazon US· 1h 20m
$21.59/TB Used

Genuine HUH721212AL4200 12TB HDD 7200 RPM SAS 12Gb/s LFF Drive Original

12 TB Internal 3.5"

SAS interface. Needs a host bus adapter, it will not plug into a normal motherboard.

$259.08 Amazon US· 2h 14m
$21.66/TB Used

HPE 12 TB Hard Drive - 3.5" Internal - SAS (12Gb/s SAS)

12 TB Internal 3.5"

SAS interface. Needs a host bus adapter, it will not plug into a normal motherboard.

$259.95 Amazon US· 2h 43m

How to Choose

Here is how the two brands compare across the factors that actually matter.

NAS drives

WD Red Plus (CMR) competes with Seagate IronWolf. Both are rated for 1–8 bay NAS use with 180 TB/year workload. Pricing fluctuates. Check both and buy whichever is cheaper at your target capacity.

Enterprise drives

WD Ultrastar competes with Seagate Exos. Both offer 5-year warranties, 550 TB/year workload ratings, and vibration sensors for high-density enclosures. Refurbished Exos and Ultrastar drives dominate the used market.

Warranty and RMA

Both brands offer similar warranty terms (2–3 years consumer, 5 years enterprise/Pro). RMA experiences vary by region. Check warranty transfer policies if buying from third-party sellers. Some warranties are non-transferable.

Recording technology

Both brands use SMR in some consumer models. Always verify CMR vs SMR for your specific model. Brand alone does not guarantee recording technology. NAS and enterprise lines from both brands are CMR.

Frequently Asked Questions

Is WD or Seagate more reliable?

Neither brand has a decisive reliability advantage. Backblaze publishes quarterly failure data from their datacenter fleet and as of 2025–2026 both WD and Seagate enterprise drives show annual failure rates between 0.5–2.5% depending on model and age. Individual model selection within each brand matters more than the logo. Pick the cheaper drive at your target capacity from equivalent tiers.

What are the equivalent NAS drive tiers between WD and Seagate?

WD Red (SMR) competes with Seagate IronWolf for basic NAS. WD Red Plus (CMR) is the closer match to IronWolf for NAS workloads. WD Red Pro and Seagate IronWolf Pro are the premium NAS tiers for heavy workloads and larger bay counts. On the enterprise side, WD Ultrastar competes with Seagate Exos.

Do WD and Seagate offer the same warranties?

Consumer drive warranties are similar: 2–3 years across both brands. Enterprise and Pro NAS lines from both offer 5-year warranties. RMA experience varies by region and individual case. Some warranties from both brands are non-transferable when bought from a third-party seller — check warranty terms before buying used or from grey-market channels.

Do Seagate or WD drives use SMR recording?

Both brands use SMR in some consumer models. Neither brand is SMR-free across all product lines. NAS and enterprise lines (IronWolf, IronWolf Pro, Exos, WD Red Plus, WD Red Pro, Ultrastar) are CMR. Standard desktop lines (Seagate Barracuda at some capacities, WD Blue, WD Red at smaller sizes) have included SMR variants. Always verify the recording technology for the specific model and capacity you are buying, not just the product line name.

Which brand is better for a NAS: WD or Seagate?

Compare specific equivalent models: WD Red Plus vs Seagate IronWolf, or WD Red Pro vs Seagate IronWolf Pro. Both are designed for NAS use with similar workload ratings. The tables on this page rank drives from both brands side by side by price per TB — buy whichever is cheaper at your target capacity on the day you shop.