Prime Big Deal Days 2026: what the category growth numbers do and don't tell UK sellers

One agency estimate says UK third-party sales grew 27.5% year on year in Prime Big Deal Days week, twice the pace of Amazon's own retail. Here is what that number is worth before you finalise Black Friday.

By Method FBA Editorial · Published 23 October 2026

Amazon has not published official figures for October's Prime Big Deal Days. The numbers below come from a single industry report, written up by an Amazon agency from its own tracking of around 1.6 million products. Amazon has not confirmed them. Treat them as directional, not audited.

The short answer

The estimate is a useful rough read on where buyer demand showed up in early October. It is not a forecast for your account, and it is not a reason to change your Black Friday plan on its own. Your own event numbers, your stock depth and your margin after discounts matter more than a market-level percentage.

The reported numbers (estimates, not Amazon data)

The figures come from ChannelX's 22 October write-up of Venture Forge's analysis, covering the Amazon UK event week of 4-10 October 2026 (the deals ran on 6 and 7 October). Estimated UK third-party (3P) sales grew 27.5% on the same week of last year's event, against 13.9% growth for Amazon's own retail (1P). Total Amazon UK takings for the week were estimated at £1.06bn, up from £864m a year earlier.

3P grew faster than 1P in eight of the ten categories tracked. Computers & Accessories was the only major category to shrink overall, down about 20%, mostly in tablets and laptops. On discounting, 1P did the deeper cutting: an average price cut of 6.3% against 3.5% for 3P, and 32% of 1P event sales came from cuts of 10% or more, against 17% for 3P. Among brands tracked in both years, brands selling mostly through 3P grew 41%, against 15% for mostly-1P brands.

What these numbers do not tell you

• The denominator. Growth percentages say nothing about the size of each category. Ten percent growth in a large category can be worth more than twenty percent in a small one.
• Who grew. Averages hide the spread. Some sellers in a "growing" category will have shrunk; some in a "flat" category will have doubled.
• Methodology. The estimate is not audited and comes from an agency that sells services to sellers. That does not make it wrong; it means you should not treat it as fact.
• Profitability. Sales growth at deep discounts can still be a loss. The report says nothing about margin.

A practical self-audit before Black Friday

Use your own October event data first, market estimates second.

1. Compare against your own baseline. Pull your sales and sessions for the 4-10 October event week against a comparable non-event period. That is the only growth number that describes your account.
2. Check stock depth on hero SKUs. If an event-level demand spike repeats in November, do you have the units? FBA inbound lead times tighten through November.
3. Price the discount before you run it. Work out margin at your planned Black Friday price including fees and any coupon cost, not at your normal price.
4. Decide which SKUs not to discount. The estimate does not oblige you to discount everything. The report itself suggests 3P sellers grew while cutting prices less than 1P did.
5. Set ad budget pacing now. Event weeks burn budget early. Decide daily caps before the event starts.

One dated reminder for FBM sellers

If you fulfil any orders yourself, Amazon expects a Business Hour Delivery Rate of 90% or higher from 30 September 2026 for qualifying shipments to Amazon Business customers, with listing deactivation possible from 30 October. See our separate guide: Amazon FBM Business Hour Delivery Rate, UK.

Primary source

ChannelX, "Prime Big Deal Days 2026: 3P grew twice as fast as 1P, and discounted less" (22 October 2026), citing Venture Forge analysis of around 1.6 million products: channelx.world/2026/10/prime-big-deal-days-2026-3p-grew-twice-as-fast-as-1p-and-discounted-less

All growth figures in this article are estimates from that report, not Amazon data.