Best 18 TB Hard Drives
18 TB is a popular capacity sweet spot for NAS builders, homelab enthusiasts, and small-business storage. It offers strong density per bay slot without the price premium of cutting-edge 20-24 TB models. At this capacity point, you will find mature, well-proven models from both Seagate and Western Digital across enterprise, NAS, and general-purpose lines.
Why 18 TB?
18 TB drives hit a practical balance: enough capacity to meaningfully reduce the number of bays needed, but typically priced lower per TB than 20 TB+ models because they use established platter technology. For a 4-bay NAS, four 18 TB drives give you 72 TB raw — or ~54 TB usable in RAID 5.
Prices updated hourly from Amazon US and UK. All links go directly to the retailer.
Best Value 18 TB Drives
All new 18 TB hard drives ranked by price per terabyte. The best deals across enterprise, NAS, and standard lines.
WD Elements 18TB Desktop USB 3.0 External Hard Drive with the SanDisk Ultra 256GB USB 3.0 Flash Drive
MDD MAXDIGITALDATA MDD 18TB 7200RPM 256MB Cache SAS 12.0Gb/s 3.5inch Internal Enterprise Hard Drive (MDD18TSAS25672E) - [Not a SATA HDD]
WD 18TB Elements Desktop External Hard Drive - USB 3.0, Black
Toshiba N300 18TB Internal NAS Hard Drive, 3.5’’ SATA HDD, 7200 RPM, 24/7 Operation, Supports 1-8 bay systems, 512MB Cache, 180TB/Year workload, 3yr Warranty (HDWG51JUZSVA).
MDD (MDD18TSATA25672DVR) 18TB 7200RPM 256MB Cache SATA 6.0Gb/s 3.5inch Internal Surveillance Hard Drive - 3 Years Warranty
Toshiba MG09 MG09SCA18TE 18 TB Hard Drive - Internal - SAS [3Gb/s SAS]
Toshiba N300 18TB NAS 3.5-Inch Internal Hard Drive - CMR SATA 6 Gb/s 7200 RPM 512 MB Cache - HDWG51JXZSTA
Western Digital HDD Gold 18 TB SATA 512 MB 3.5 Inch
Enterprise 18 TB Drives
Seagate Exos and WD Ultrastar 18 TB models for server and datacenter use. 24/7 rated with 5-year warranties and high workload endurance.
Seagate Exos X18 Enterprise Class, 18TB, Enterprise Internal Hard Drive, SATA, 3,5" 6Gbit/s, 128MB cache ((ST18000NM000J)
Western Digital Ultrastar DC HC550 Enterprise Hard Drive 18TB (3.5" SATA 6Gbps, SAS 12Gbps, 7200RPM, 512MB Cache)
Seagate Exos X18 ST18000NM001J 18 TB Hard Drive - Internal - SATA (SATA/600)
Western Digital Ultrastar DC HC550 18 TB Hard Drive - 3.5 Internal - SATA
Western Digital Ultrastar DC HC550 18 TB Hard Drive - 3.5" Internal - SATA
Seagate Exos X20 18TB Internal Hard Drive - 3.5 Inch Hyperscale 12GB/s SAS HDD, 7,200 RPM, 2.5M MTBF, 512e and 4Kn FastFormat, Low Latency with Enhanced Caching (ST18000NM000D)
Western Digital Ultrastar DC HC550 18 TB Hard Drive - 3.5" Internal - SAS (12Gb/s SAS)
Seagate ST18000NM003D 18TB Exos X20 SATA Hard Drive, 3.5" HDD, SATA 6Gb/s, 7200rpm, 256MB Cache, 512E, 4.16ms, NCQ
NAS 18 TB Drives
IronWolf and WD Red 18 TB models designed for always-on NAS enclosures. NAS firmware optimisations for RAID and multi-bay vibration.
Refurbished 18 TB Drives
Used and recertified 18 TB drives at reduced prices. Enterprise datacenter pulls that offer strong value for non-critical storage and homelab use.
Western Digital HDD Gold 18 TB SATA 512 MB 3.5 Inch
WD 18TB Elements Desktop External Hard Drive - USB 3.0, Black
Western Digital WD WUH721818AL5204 18TB SAS 12Gb/s 7.2K RPM 512M 0F38353 512e/4Kn SE HDD
MDD 2018 MDD18TS25672NAS 18TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5'' Internal NAS Hard Drive - 5 Years Warranty (Renewed)
Seagate Exos X18 Enterprise Class, 18TB, Enterprise Internal Hard Drive, SATA, 3,5" 6Gbit/s, 128MB cache ((ST18000NM000J)
SanDisk Professional 18TB G-Drive Enterprise-Class External Desktop Hard Drive - 7200RPM Ultrastar HDD Inside, USB-C (10Gbps), USB 3.2 Gen 2, Mac Ready - SDPHF1A-018T-NBAAD
MDD MAXDIGITALDATA MDD (MD18TSATA25672NAS) 18TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5-inch Internal NAS Hard Drive - 5 Years Warranty (Renewed)
Western Digital 18TB WD Purple Surveillance Internal Hard Drive HDD - SATA 6 Gb/s, 256MB Cache, 3.5" - WD180PURZ
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Best HDD Deals Right Now
Find the best hard drive deals sorted by price per terabyte. Compare new and refurbished HDDs across Amazon US and UK, updated hourly.