What is the difference between WD Red and WD Red Plus?
WD Red Plus is CMR; the original plain WD Red (2–6 TB EFAX models) was SMR. WD created Red Plus specifically to mark the CMR NAS drives after the SMR controversy. For a NAS, buy WD Red Plus (or Red Pro) — the plain WD Red's SMR recording is unsuited to RAID. Larger Reds (8 TB+) were already CMR.
Last verified July 22, 2026 · 2 official sources checked Updated
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The difference is recording technology. After WD quietly shipped some plain WD Red drives as SMR, it introduced WD Red Plus to clearly designate the CMR NAS drives — same NAS positioning, but conventional recording.
The split
- Plain WD Red (WD20–60EFAX, 2–6 TB): SMR. Poorly suited to RAID rebuilds.
- WD Red Plus: CMR across capacities — the NAS drive to buy.
- WD Red Pro: CMR, 7200 rpm, higher workload rating and 5-year warranty, for busier or larger NAS units.
Confusingly, the higher-capacity plain Reds (8 TB and up) were CMR even before the split, but the safe rule today is simply: buy Red Plus or Red Pro and you are guaranteed CMR.
Does the difference matter?
Yes, for a NAS. SMR drives rewrite overlapping tracks and slow dramatically under sustained writes, which is exactly the load of a RAID rebuild. A CMR Red Plus rebuilds predictably; an SMR plain Red can stall. Unless you have a specific single-drive, write-light use, choose CMR. The table lists in-stock WD Red Plus drives.
WD Red Plus / Red Pro (CMR) drives in stock, by CA$/TB
Live Amazon.ca prices in CAD, ranked by price per terabyte. The Recording column is verified against manufacturer documentation.
Related questions
Sources
Every technical claim on this page is checked against manufacturer and standards documentation. Dates are when each source was last reviewed.
- Western Digital — WD Red Plus / Red Pro product & recording-tech documentation — checked 2026-07-22
- Western Digital — Internal drives CMR/SMR statement — checked 2026-07-22