Amazon Seller Briefing: September 21, 2026

Amazon begins requiring Seller Central passkeys on a rolling basis from about September 29, 2026, staged account by account. Once enrolled, passwords no longer work for ordinary login. A new Quantity variation theme covers 193 product types, and Accelerate streams free on the Seller Forums September 22-24.

Published September 21, 2026 · Seller Signal daily briefing

Good morning, sellers! Welcome to September 21, 2026's edition. Today: Seller Central passkeys become mandatory from about September 29, a new Quantity variation theme reaches 193 product types, and Amazon Accelerate streams free on the Seller Forums starting tomorrow. Let's dive in…

Data gathered at 6:05 AM ET, September 21, 2026.

1. Top Story of the Day

Amazon starts requiring Seller Central passkeys, account by account, from about September 29

What happened: An Amazon email dated September 15, 2026 told sellers: "Starting in two weeks, passkeys will start to be required on a rolling basis for Amazon accounts." Two weeks out is about September 29, 2026. Amazon describes a passkey as "a secure, passwordless way to sign in using your device's built-in authentication — like fingerprint, face recognition, or PIN." It covers Seller Central and Amazon.com accounts.

Once an account is enrolled, its password stays available for recovery but is no longer accepted for ordinary login. There is no universal cutoff — the rollout is staged account by account. Amazon says setup takes under two minutes and recommends passkeys on two devices, which sync through an Apple, Google or Microsoft account. On shared accounts, each additional person must be registered as a secondary user with their own passkey, on an email address not used on another Amazon account.

None of this is unannounced: Amazon warned in June 2026 that passkeys would become required, and they arrived as an optional method for December 2, 2025. EcomCrew reported the mandate September 20.

Why it matters: The failure mode is a lockout, and the timing is the problem. Enrollment lands around Prime Big Deal Days on October 6-7 and the October 15 start of FBA holiday peak fulfillment fees — when losing pricing or bid controls costs the most.

Expert take: The staged rollout is what makes this dangerous rather than tedious. A seller who reads "September 29" as a deadline, sees nothing change and concludes it does not apply gets enrolled mid-deal-week instead. The secondary-user rule is the structural trap: an agency, VA or warehouse manager sharing one login cannot add a second passkey to it — they need their own secondary user, on an email untouched by any other Amazon account. Teams sharing credentials meet that constraint the moment the password stops working. It compounds the Manage Services reauthorization covered here September 16: both reset account access on deadlines Amazon delivers individually.

Action items:

Create a passkey on two devices for the primary login now, rather than waiting for the notice.
Register everyone who signs in — staff, agency, VA — as a secondary user on an unused email.
Confirm which inbox receives the enrollment notice, and do not treat September 29 as fixed.

Sources: EcomCrew, September 20, 2026; seller email at Sellers Ask Sellers; Amazon Seller Forums, December 2, 2025.

2. Amazon Policy & Program Updates

Catalog & Listings

Amazon staff account News_Amazon announced a new Quantity variation theme on August 29, 2026, covering 193 product types, primarily in hardlines. Single packs display as "X count"; multipacks as "X count (Y packs of Z)." Two attributes drive it: unit count, the total individual units, mandatory, and number of packs, required only for multipacks. Amazon says it separates quantity from attributes like size or color, "helping customers quickly understand what they're purchasing." It is optional for new and existing listings, and Amazon states: "We'll expand this to other categories later in 2026."

The practical read: quantity stops being buried in a size field, so a multipack with a wrong unit count now misstates itself on the detail page rather than sorting oddly. Verify unit count against the physical carton first. (Amazon Seller Forums; EcomCrew, September 20, 2026)

Events & Access

Amazon Accelerate 2026 streams free on the Seller Forums for the first time, per a pinned thread posted about September 18, 2026. Three sessions run September 22-24:

Tuesday, September 22, 7:00 PM ET — fireside chat with Mary Beth Westmoreland, VP of Worldwide Selling Partner Experience, and Amit Agrawal, SVP of Worldwide Selling Partner Services.
Wednesday, September 23, 12:00 PM ET — General Session #1.
Thursday, September 24, 12:00 PM ET — General Session #2.

A new pinned thread goes live on the forums homepage for each session; sellers watch there and post questions while the stream runs. Amazon lists the topics as new AI listing tools, updated FBA programs, advertising features and international expansion. In-person registration ran $599 plus sales tax; the streams are free. (Amazon Seller Forums)

3. Marketplace Opportunities & Threats

eBay sketches a list-once-sell-everywhere plan for 2027, without specifications

At eBay Open UK, eBay described a 2027 goal of letting sellers create one listing and reach international buyers while eBay handles more of the translation, localization and shipping work, EcomCrew reported September 20, 2026 from Value Added Resource's coverage. No specifications, pricing or rollout dates were published.

The part with terms attached is live: eBay International Shipping, or eIS, reaches buyers in more than 195 countries with international selling fees waived, and eBay began migrating eligible UK sellers off the Global Shipping Programme onto it in phases in August 2026. Eligibility requires items physically in the UK, listed on ebay.co.uk, in eligible categories and valued at no more than £900 — that ceiling decides whether your catalog travels. (EcomCrew)

4. Seller Community Pulse

A thread on the Sellers Ask Sellers forum running September 15-19, 2026 reproduced the passkey email and collected the first complaints — login loops, device compatibility errors, confusing setup steps. One poster wrote: "There are complaints all over the Reddit website about this new ineffective passkey setup process." Another noted that when the optional system appeared months earlier, "no one could set it up."

That is the argument for enrolling deliberately, on a day you can afford to troubleshoot. (Sellers Ask Sellers)

5. Looking Ahead

September 21: TikTok Shop EU-UK cross-border pilot opens; full launch October 19.
September 22: Prime Big Deal Days deal submissions close.
September 22-24: Amazon Accelerate 2026 in Seattle, streaming free on the Seller Forums; CBP Entry Type 13 test opens in ACE September 22.
September 25: FTC comment deadline on personalized pricing, docket FTC-2026-1057.
September 28-30: Amazon unBoxed 2026 at Moscone West, San Francisco.
About September 29: Amazon passkeys start being required on a rolling basis.
September 30: Business Hour Delivery Rate takes effect for US seller-fulfilled Amazon Business orders — 90% or higher.
October 6-7: Prime Big Deal Days in 22 countries.
October 14, 21 and 28: BFCM inbound deadlines — AWD, minimal splits, Amazon-optimized splits.
October 15: FBA holiday peak fulfillment fees begin, averaging $0.32 per unit through January 14, 2027; eBay Live leaves eBay seller metrics.
October 20: Black Friday Week and Cyber Monday deal submission closes.
October 25: Amazon Shipping peak demand surcharges begin, through January 16, 2027.
November 2: Commercial liability insurance changes take effect for 11 enhanced-safety categories — $1 million cover.
January 11, 2027: Amazon's bundling policy changes; noncompliant bundles are deactivated.

All dates 2026 unless stated; Q4 deadlines per Amazon Seller Forums.