Mechanical hard disk drives (HDD) are typically used for mass storage, NAS enclosures included. They offer the widest range of capacities, the best value in terms of $ per GB, and decent performance. Solid-state drives (SSD) are the next step up, more than doubling bandwidth (and price). An advantage of using SSDs inside a NAS is the lack of any moving parts, longer life span, and zero vibrations and noise emitted from each drive. Here are my favorite SSDs for use inside NAS.

• Best SSD for NAS

  Western Digital Red SA500

  $0.14 per GB

  The Western Digital Red SA500 are specifically designed for use inside NAS enclosures. They offer better performance over mechanical HDDs and have no moving parts. This is a good choice if you want better performing connected storage.

  $70 at Amazon $75 at Newegg
• Best M.2 SATA NAS SSD

  Western Digital Red SA500 M.2

  $0.14 per GB

  The Western Digital Red SA500 M.2 is essentially an M.2 version of the same 2.-inch SATA SSD. It offers the same performance but is only available in 500GB, 1TB, and 2TB capacities.

  $70 at Amazon $80 at Newegg
• Best M.2 NVMe NAS SSD

  Western Digital Red SN700

  $0.14 per GB

  Western Digital's Red SN700 SSDs are M.2 NVMe drives with speeds of up to 3,100MB/s. That's a considerable performance boost over SATA SSDs with a maximum read speed of just 500MB/s. These are also great for NAS caching.

  $70 at Amazon $70 at Newegg
• Best budget NAS SSD

  Western Digital Blue SSD

  $0.11 per GB

  Western Digital Blue is a range of affordable SSDs that range between 250GB and 4TB. They interface with a SATA port just like HDDs and offer transfer speeds of up to 555MB/s.

  $55 at Amazon $55 at Newegg
• Best value NAS SSD

  Samsung 870 QVO SATA III 2.5-inch SSD

  $0.18 per GB

  This SSD from Samsung is massive. It has ample space for all your favorite games, media, and then some. It's pricey, but this discount makes it easier to digest.

  $112 at Amazon $125 at Samsung $117 at Newegg
• Best capacity NAS SSD

  TeamGroup EX2

  $0.07 per GB

  TeamGroup's impressive EX2 Elite range of SSDs are designed for use inside desktop and laptop PCs, but there's the option for a 16TB drive. This surpasses waht's available with specific NAS SSDs and thus we'd recommend this for maximum flash capacity.

  $34 at Amazon $34 at Newegg
• Best NAS SSD for caching

  Intel Optane P4801X

  If you're serious about working with big data and need a caching drive to improve system performance, look no further than the Intel Optane P4801X. It's a reliable, heavy-duty SSD that packs a mighty punch.

  $244 at Amazon

Choosing the best SSD for NAS

Picking the right solid-state drive for your NAS largely comes down to how much data you have to store on the enclosure. SSDs designed for use inside NAS don't have a vast choice of capacities to match NAS HDDs and often top out at 4TB. Desktop-class SSDs that are used inside PCs do support capacities of 8TB, but these aren't certified for server usage and your mileage will vary depending on how much data will be written to the drive on a daily basis.

I'd recommend the Seagate IronWolf or Western Digital Red series of SSDs for NAS though these do cost a premium when compared against desktop-class SSDs from the same brands, Samsung, TeamGroup, among others. If you want the cheapest drive configuration, it's possible to pick up smaller SSDs for as little as $30. TeamGroup does have a whopping 16TB 2.5-inch SSD available for just shy of $2,000 for maximum NAS capacity.

Intel's Optane range of solid-state drives is great for caching data and other difficult scenarios. The performance of a NAS can be improved through the upgrading (and expansion) of system memory, but should that not be possible and M.2 slots are available, SSDs can be used for data caching. Kitting out your NAS with SSDs will not be a cheap endeavor, but my roundup of drives will ensure you're buying the very best.