Best NAS hard drives for Synology
Synology DiskStations are happiest on NAS-rated CMR drives built for 24/7 duty. SMR drives can technically work but risk timeouts during an SHR or RAID rebuild, so this list sticks to CMR NAS and NAS-Pro drives only.
Cross-check Synology's compatibility list for your exact model before buying - newer units can warn or limit features on unlisted drives - but anything here is a sound starting point.
| Drive | Capacity | Tech | Class | Interface | AFR | €/TB | Price | |
|---|---|---|---|---|---|---|---|---|
| 1 |
WD240KFGX
WD Red Pro
|
24 TB | CMR | NAS-Pro | SATA | - | €43.29 | €1,039 |
| 2 |
ST24000NT002
Seagate IronWolf Pro
|
24 TB | CMR | NAS-Pro | SATA | - | - | - |
| 3 |
WD221KFGX
WD Red Pro
|
22 TB | CMR | NAS-Pro | SATA | - | - | - |
| 4 |
ST22000NT001
Seagate IronWolf Pro
|
22 TB | CMR | NAS-Pro | SATA | - | €34.55 | €760 |
| 5 |
WD201KFGX
WD Red Pro
|
20 TB | CMR | NAS-Pro | SATA | - | €45.00 | €900 |
| 6 |
ST20000NT001
Seagate IronWolf Pro
|
20 TB | CMR | NAS-Pro | SATA | - | €36.50 | €730 |
| 7 |
WD181KFGX
WD Red Pro
|
18 TB | CMR | NAS-Pro | SATA | - | €57.17 | €1,029 |
| 8 |
ST18000NT001
Seagate IronWolf Pro
|
18 TB | CMR | NAS-Pro | SATA | - | €38.89 | €700 |
| 9 |
WD161KFGX
WD Red Pro
|
16 TB | CMR | NAS-Pro | SATA | - | €71.18 | €1,139 |
| 10 |
ST16000NT001
Seagate IronWolf Pro
|
16 TB | CMR | NAS-Pro | SATA | - | €42.65 | €682 |
Ranked by measured failure rate (Backblaze AFR). $/TB shows once live prices are wired.
Choosing drives for a Synology DiskStation
Check the compatibility list first
Synology publishes a supported-drive list per model. A listed drive sidesteps the "unverified drive" warnings on newer DSM units and keeps every feature available. The drives ranked above are solid NAS-class picks, but the compatibility list for your specific box is the final word.
Stick to NAS-rated CMR
NAS lines like WD Red Plus and Seagate IronWolf are tuned for the things a DiskStation does to a drive: constant vibration from neighbouring bays, a 24/7 duty cycle, and RAID error-recovery timing (TLER/ERC). That last one earns its keep - without it, a drive that pauses to recover a sector can get wrongly flagged as failed and kicked from the volume.
Match sizes within a volume
A RAID volume is capped by its smallest member, so matched capacities keep things simple and predictable. Synology's SHR loosens this if you expect to mix sizes over time, but a set of identical CMR drives is still the cleanest way to build a pool.
Frequently asked questions
- Do Synology NAS units need special drives?
- Not special, but they should be NAS-rated CMR drives designed for continuous operation and vibration tolerance in multi-bay enclosures. Desktop and SMR drives are not recommended.
- Can I mix drive brands and sizes in a Synology?
- You can, but each volume is limited by its smallest drive, and mixing is best avoided in a single RAID group. For SHR you can mix sizes more flexibly, though matched CMR drives give the most predictable performance.
- Why avoid SMR in a Synology?
- SMR drives can become very slow under sustained writes, which may cause a RAID rebuild to stall or the drive to drop out of the array. CMR drives avoid this failure mode entirely.