Prime Big Deal Days NVR and Surveillance Drive Deals

The top of the range: 18TB

The highest tier in stock today is 18TB (2 listings), cheapest at $28.33/TB. The tier below, 16TB, is cheapest at $34.37/TB.

Today the top tier is not dearer per unit: 18TB is 18% cheaper per TB than 16TB. A high price is still not a verdict - read the badge for the specific listing.

The workload ladder, as each maker rates it

Ratings are the makers' own, read at source 15 September 2026; we measure none of them. The commonly repeated ~55TB/year desktop figure is not in Seagate's current BarraCuda sheet, which states 120TB/year - so 120 is what we print. Above the rating, Seagate's manual says: “Workloads exceeding the annualized rate may degrade the drive MTBF and impact product reliability.” (SkyHawk AI Serial ATA Product Manual, Rev. E (100855892, March 2021)). WD's own datasheets (WD Purple, November 2025; WD Purple Pro, July 2025) define how the workload rate is calculated but do not state a consequence for exceeding it, in any document we could render. We report that absence rather than assume a consequence we have not found WD state.

Sizing by camera count (computed live)

Inputs, each labelled with where it comes from: 3.2Mbps per camera - WD's own reference stream (single stream, 1080p, h.265, 25fps, WD Purple / WD Purple Pro data sheets (footnote 3)); 24 hours a day - continuous recording, the basis both makers annualise their ratings on; 30 days retained - our default, not a vendor figure. The drive column is the cheapest in-stock CMR surveillance drive that both holds the retention window and carries a rating above the annual writes. It is one drive: no recorder listing states a bay count, so we assume none.

The honest tier answer: at the reference bitrate one camera writes 12.6TB a year, so the 180TB/year standard rung covers 14 cameras recording continuously and the 550TB/year AI tier covers 43. Most installs sit far below the AI tier's rating, so the cheaper drive is usually the correct one. We do not hold a new CMR standard-rung drive and a new CMR AI-tier drive at the same capacity today, so there is no like-for-like price gap to print.

Recorders by channel count: 8-channel NVRs · 16-channel NVRs.

What to watch in surveillance storage this event

Surveillance storage is two purchases that are usually made at once: a recorder (an NVR) and the drive that goes inside it. Both are on this page, in separate tables, because they are priced and badged separately and because the recorder listings in this category are unusually inconsistent about what is in the box. Every NVR row carries its drive-presence state exactly as the listing gives it - diskless, a drive bundled (with the capacity the listing states), or not stated. A recorder whose listing does not say is not assumed to be either; a buyer who guesses wrong either pays for a second drive or receives a recorder that cannot record.

The drive table lists every surveillance-class drive we track that is in stock today - Seagate SkyHawk and SkyHawk AI, WD Purple and WD Purple Pro - one row per drive, its cheapest offer, with the condition shown. Each row carries two labels: the workload rating its maker publishes for that line, and its recording technology. Where we do not hold a recording technology for a drive, the row says so and the drive is excluded from every sizing answer on this page. That is deliberate. A drive we cannot confirm as CMR is not one we will put inside a recommendation, even an arithmetic one.

What we do not do is assemble a recorder-plus-drive basket. Not one NVR listing we track states its drive bay form factor or its bay count, and a basket that assumed a 3.5-inch bay would be an inference dressed as a specification. The recorders and the drives are each priced and badged here; matching them is a check against the recorder maker's own documentation that only the buyer can make for the exact model.

The workload ladder, as the makers publish it

Hard drive makers rate surveillance drives by annual workload - terabytes transferred per year - because a recorder writes continuously and a desktop drive is not designed for that duty. The rungs below are the makers' own figures from their current data sheets, each cited in the ladder table on this page with the document and its date. They are ratings, not measurements, and we measure none of them.

One correction to a commonly repeated figure. Desktop drives are often said to be rated around 55TB a year. Seagate's current 3.5-inch BarraCuda data sheet, the one covering the 16 to 24TB models, states 120TB a year, and that is the figure we print. The 55TB number is not in the current sheet we could read, so it is not on this page.

The ladder runs from the desktop rung through standard surveillance drives (SkyHawk, and WD Purple at 180TB a year for its current retail part numbers), a higher WD Purple rung at 360TB a year that WD states only for three specific part numbers, to the AI tier - SkyHawk AI and WD Purple Pro - at 550TB a year. Seagate's own product manual states what happens above the rating: workloads exceeding the annualised rate may degrade the drive's reliability. WD's data sheets define the rate but state no consequence for exceeding it, and we report that absence rather than fill it.

Retention arithmetic, with every default labelled

How much drive you need is arithmetic: cameras, times bitrate, times hours recorded per day, times the number of days you want to keep. The only input that needs a source is the bitrate, and the only vendor-published per-camera figure we could render is WD's own: 3.2 megabits per second for a single 1080p H.265 stream at 25 frames per second, from the footnotes of the WD Purple and Purple Pro data sheets. That is the default in the table on this page and in our surveillance storage calculator. Real bitrates vary widely with resolution, codec, scene activity and encoder settings; use your own camera's documented or observed figure if you have it.

Hours per day defaults to 24 - continuous recording, which is also how both makers annualise their workload ratings in their own footnotes. Retention defaults to 30 days, and that one is our choice, not a vendor's: it is labelled as ours everywhere it appears. Doubling retention doubles the capacity figure and changes nothing about the workload tier, because a recorder that keeps 7 days and one that keeps 90 days write the same volume per year; one of them simply overwrites sooner.

The two numbers therefore answer two different questions. Capacity answers how big the drive must be to hold your retention window. Annual write volume answers which workload rung the drive needs. Buy the capacity your retention needs, on the cheapest rung whose rating is above your annual write volume.

The honest tier answer

At the reference bitrate, a small home or small-office system sits far below the AI tier's rating. The sizing table on this page shows the annual writes for 4, 8 and 16 cameras - the channel counts the recorders in this category are sold at - against each rung, computed from the same inputs, and where each rung runs out.

The AI tier exists for a reason, and it is not a scam: it is rated for more simultaneous streams and for recorders that run analytics on the stored video, and it carries a longer warranty on the makers' own terms. It suits a large camera count, high-bitrate cameras well above the reference figure, or a recorder that runs AI analytics across many streams. For most installs the cheaper rung is the correct buy, and the price comparison on this page shows what the difference costs today.

The trap: paying for a rating you will never use

The event trap in surveillance is the premium drive on a percent-off headline. An AI-tier drive at a discount can still cost materially more per terabyte than a standard surveillance drive of the same capacity, and an 8-camera home system will never approach the rating that premium buys.

Size first: cameras, bitrate, hours, days. Pick the cheapest rung whose rating clears your annual writes, confirm the drive is CMR, and only then read the badge on the listing you have chosen.

Frequently asked questions