Best 20 TB Hard Drives
20 TB drives sit at the high end of mainstream capacity, offering maximum density for builds where every bay slot counts. These are almost exclusively helium-sealed enterprise or NAS models, delivering excellent sustained throughput and power efficiency per terabyte. If you are building dense storage (whether a JBOD shelf, a high-capacity NAS, or a Plex archive) 20 TB drives let you pack more usable storage into fewer slots.
Why 20 TB?
20 TB drives deliver roughly 11% more capacity than 18 TB at a modest price premium. But check the per-TB cost carefully, as 18 TB sometimes wins on value. The sweet spot is when 20 TB models are on sale or when bay slots are your limiting factor. Four 20 TB drives in RAID 5 give you ~60 TB usable.
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 MDD MDD (MDD20TSATA25672E) 20TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5-inch Internal Enterprise Hard Drive - 5 Years Warranty (Renewed), 20 TB used, at $489.99 ($24.50/TB) on Amazon.com. Check the current price.
Best Value 20 TB Drives
All new 20 TB hard drives ranked by price per terabyte across brands and product lines.
MDD MAXDIGITALDATA 20TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5'' Internal Hard Drive (for NAS, Network Storage) - 5 Years Warranty
OSENTRiX BX100 20TB USB 3.2 Gen 2 USB-C External Hard Drive for Windows or MacOS Desktop PC/Laptop
BUFFALO Replacement Spare Hard Drive 20TB NAS-Grade for TeraStation 2/4/8 Bay (OP-HD20.0N)
Avolusion PRO-G1 Series 20TB USB 3.2 Gen 2 (10Gbps) USB-C External Hard Drive for Windows or MacOS Desktop PC/Laptop (Silver)
BUSlink CipherShield CSE-20TG1-U3 20TB HDD Mode 0 Encrypted Desktop Drive – 256-bit AES Hardware Encryption, FIPS 140-2, USB 3.0, HIPAA, HITECH, FERPA, TAA-Compliant
WD 20TB Elements Desktop External Hard Drive, USB 3.0 drive for plug-and-play storage - WDBWLG0200HBK-NESN
BUSlink CipherShield CSX-20TSU3KKC 20TB Colateral 2FA Dual Key Encrypted External HDD – 512-bit AES Hardware Encryption, USB 3.2 Gen 1 & eSATA, FIPS 140-2, HIPAA, HITECH, FERPA, TAA-Compliant
BUSlink CSX-20TSU3KKB 20TB HDD 2FA Bilateral Dual Keys 512-bit AES USB 3.2 Gen 1 (3.0) /eSATA CipherShield FIPS 140-2 HIPAA Hardware Encrypted External Drive
Enterprise 20 TB Drives
Exos and Ultrastar 20 TB models for datacenter and server workloads. Maximum density with 24/7 endurance ratings.
Seagate 20TB Exos Enterprise Hard Drive | SATA (ST20000NM002H)
Seagate Exos X20 ST20000NM007D 20TB 7.2K RPM SATA 6Gb/s 3.5in Hard Drive
Seagate Exos X20 ST20000NM000D 20 TB Hard Drive - Internal - SATA (SATA/600) - Conventional Magnetic Recording (CMR) Method - Storage System, Video Surveillance System Device Supported - 7200rpm - 285
Seagate Exos X24 20TB Enterprise Internal Hard Drive HDD - 12GB/s SAS 7200RPM 2.5M MTBF (ST20000NM002H)
SAS interface. Needs a host bus adapter, it will not plug into a normal motherboard.
Western Digital 0F38652 Ultrastar DC HC560 20TB Hard Drive
SAS interface. Needs a host bus adapter, it will not plug into a normal motherboard.
[Amazon.co.jp Limited] Western Digital Ultrastar DC HC550 20TB Business Internal Hard Drive CMR 3.5 Inch SATA 7200rpm OptiNAND HelioSeal Heavy Duty WUH722020CLE6L4-AJP Eco Package
Seagate Exos X24 20TB 3.5" 6 Gb/s SATA III Internal Hard Drive 4pk
Seagate Exos X24 20TB 3.5" 12Gb/s SAS III Internal Hard Drive 4pk
SAS interface. Needs a host bus adapter, it will not plug into a normal motherboard.
NAS 20 TB Drives
IronWolf and WD Red 20 TB models for high-capacity NAS builds. NAS firmware with vibration tolerance and RAID-optimised error recovery.
Refurbished 20 TB Drives
Recertified 20 TB enterprise pulls at significant discounts. High-density storage for homelabs, archives, and Plex libraries on a budget.
MDD MDD (MDD20TSATA25672E) 20TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5-inch Internal Enterprise Hard Drive - 5 Years Warranty (Renewed)
MDD MAXDIGITALDATA (MD20TSATA25672NAS 20TB 7200RPM 256MB Cache SATA 6.0Gb/s 3.5inch Internal NAS Hard Drive (Renewed)
MDD (MDD20TSATA25672DVR) 20TB 7200RPM 256MB Cache SATA 6.0Gb/s 3.5-Inch Internal Surveillance Hard Drive - 3 Years Warranty (Renewed)
Avolusion M5 Series 20TB USB 3.0 External Hard Drive for WindowsOS Desktop PC/Laptop (Renewed)
MDD MAXDIGITALDATA MDD 20TB 7200 RPM 256MB Cache 3.5-inch Internal Enterprise Hard Drive - 5 Years Warranty (Renewed)
Western Digital WD Ultrastar 20TB Internal Hard Drive WD200EDGZ 3.5 Inch HDD SATA 6Gb/s 7200RPM 512MB Cache (Renewed)
Avolusion PRO-H1 20TB 7200RPM USB 3.2 Gen2 (10Gbps) External Hard Drive (for Windows or MacOS Desktop PC/Laptop) (Renewed)
Avolusion PRO-T5 Series USB 3.0 External Hard Drive for WindowsOS Desktop PC/Laptop (White) - 2 Year Warranty (20TB) (Renewed)
Frequently Asked Questions
Why choose a 20 TB drive?
20 TB gives you roughly 11% more capacity than 18 TB per bay, which matters most when bay slots are your limiting factor — a dense JBOD, a full NAS, or a large Plex archive. These are almost all helium-sealed enterprise or NAS models with strong sustained throughput and good power efficiency per terabyte. Four 20 TB drives in RAID 5 give about 60 TB usable.
Is 20 TB better value than 18 TB?
Check the per-terabyte cost before assuming either way. In our 2026-08-20 snapshot 20 TB ($25.00/TB) had dropped below 18 TB ($27.72/TB), so 20 TB won on both value and density per bay. The 2026 shortage keeps these tiers moving, so compare the live $/TB on this page and buy 20 TB when it is on sale or when slots are scarce.
Are 20 TB drives CMR?
Yes — 20 TB drives are helium-sealed enterprise and NAS models using CMR, safe for RAID and ZFS arrays. There are no mainstream SMR drives at this capacity.
Are 20 TB drives reliable enough to trust?
They are enterprise-class drives rated for 24/7 operation, high workloads, and 2M+ hour MTBF, so reliability is strong. But no single drive is a backup strategy — at this capacity a rebuild moves a lot of data, so run 20 TB drives in a redundant array (RAID or ZFS) and keep a separate backup copy.
New or refurbished at 20 TB?
New 20 TB drives include a 5-year enterprise warranty; refurbished pulls at this capacity are rarer and the discount is often thin (in our August 2026 data used 20 TB saved little over new). Compare the current new and used $/TB on this page — at 20 TB, new is frequently the better all-in value once warranty is priced in.
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