Amazon announced on 15 September that Prime Big Deal Days 2026 runs 6–7 October: 48 hours of Prime-member deals, starting at 12:01 a.m. PDT on 6 October in the US. For a private-label seller, most of the event is already decided — deal submissions closed on 8 September, and the last FBA inbound cutoff for the event is tomorrow, 16 September. What you still control is your price, your stock position and your ad plan, and the ad plan finally has a date to be built around.

What changed

In July Amazon published its Holiday 2026 seller calendar without saying when the event itself would run — we flagged that gap at the time. Amazon has now filled it on its own news site:

  • Dates: 6–7 October 2026, 48 hours.
  • US start: 12:01 a.m. PDT on 6 October.
  • Where: Prime members in 22 countries, including the US, the UK, Canada, Germany, France, Italy, Spain, the Netherlands, Belgium, Sweden, Poland and Ireland. Amazon’s page says dates may vary per country and gives no local start times outside the US.
  • Breadth: deals across more than 35 categories, with new deals released three times a day — at midnight, 8 a.m. and 1 p.m. PDT.

NBC Select and 9to5Toys both reported the same 6–7 October dates on 15 September.

The announcement is written for shoppers. It says nothing about sellers and sets no dates for Black Friday Week or Cyber Monday. The seller-side calendar we covered in July — reported identically by EcomCrew, Ordoro and PPC Land from Amazon’s Seller Central announcement — is where your deadlines come from:

  • Deal submissions: closed 8 September.
  • AWD inbound: 2 September.
  • FBA inbound, minimal shipment splits: 9 September.
  • FBA inbound, Amazon-optimized splits: 16 September.
  • Peak fulfilment window: 15 October 2026 to 14 January 2027 (the holiday fees we covered in July).

What it means for a private-label seller

The worst case from July didn’t happen. The risk with an undated event was that it would land after 15 October, so your deal units would be fulfilled inside the peak fee window. It won’t: the event closes on 7 October, eight days before that window opens. Orders from a two-day event should ship before 15 October — but that is an expectation, not a rule Amazon has stated, so check the fulfilment fee on your settlement report afterwards instead of assuming it.

Your event stock is decided by tomorrow. The minimal-splits cutoff passed on 9 September; only shipments on Amazon-optimized splits still have until 16 September. If a shipment isn’t already moving, it is unlikely to count. So the question is no longer “how much do I send” but “how deep can I discount the units I’ll actually have”. A deal that sells out on the first morning leaves you out of stock for the rest of the event — and out of stock is where you lose the organic rank the deal was supposed to buy.

If you didn’t submit a deal by 8 September, that route is closed. What’s left is what you control directly: your price, your coupons and your ads. The trade-off is real. Cutting your price during the event without a deal badge means paying away margin while competing against listings that have the badge and the placement. For some ASINs the honest answer is to hold price, keep ads at a sensible level, and let the event pass.

The ad ramp now has a date. In July we suggested staging budget and bid increases as a switch to flip on confirmation rather than a guess. You have your confirmation, and three weeks to use it. The cost of ramping early hasn’t changed: you pay more for clicks at normal-demand conversion rates. What changes during the event is measurement. Deal traffic converts whether or not your ad was there, so event-day ROAS will look better than the ads deserve. An ad-attributed sale is not an incremental one.

UK and EU sellers: don’t assume. Amazon’s page says dates may vary per country. Confirm the event dates and your inbound cutoffs in the Seller Central account for each marketplace you sell in, not from US coverage — this one included.

What to do about it

  • Today: check every Q4 shipment against the 16 September cutoff. Anything that isn’t going to make it is Black Friday stock now, not event stock — plan it that way.
  • Size the discount to the stock, not the other way round. Keep enough units behind the deal to stay in stock through 7 October.
  • Put the ad changes on the calendar now — the increase, and the date it reverts. The rollback is the half that gets forgotten, and event bids running into a normal week is where the margin leaks.
  • Rerun your deal break-even at standard fulfilment fees for event sales, and at peak fees for anything you expect to sell after 15 October.
  • Decide how you’ll judge the event before it starts: total sales and TACoS against the two weeks before, not ROAS in the ad console.

Sources

The event facts are confirmed on Amazon’s own page. The seller deadlines trace to Amazon’s Seller Central announcement as reported by three independent outlets; your own cutoffs depend on your shipment plan, so confirm them in Seller Central.