Deadlines for small businesses. In plain words.

Each page has the date, the official source link and a copy-paste prompt you can give your own AI agent. Always check the official source too.

Only want the ones that affect you? Use the free Deadline Finder: tick the tools you use and see just those dates.

Last checked: Oct 16, 2026.

Deadlines

Date	Deadline	Source
Oct 26, 2026 Upcoming	ChatGPT custom GPTs retire Dec 11 (affected Enterprise workspaces: new GPT creation planned to end Oct 26) Anyone who created or relies on a custom GPT. Creators can migrate GPTs to plugins.	Source: OpenAI Help Center: Custom GPT retirement and migration FAQ
Nov 1, 2026 Upcoming	EU product identifiers become mandatory for low-value e-commerce imports Sellers outside the EU who ship online orders up to €150 to EU consumers.	Source: European Commission: Guidance and legal text on temporary flat fee on low-value imports
Nov 2, 2026 Upcoming	Amazon commercial liability insurance rules Amazon sellers. Check which rules apply to your products.	Source: Amazon Seller Central announcement: New Commercial Liability Insurance Requirements effective November 2, 2026
Nov 3, 2026 Upcoming	ZenBusiness Banking closes (deposits stop Nov 3, accounts close Nov 30) ZenBusiness Banking account holders.	Source: ZenBusiness Help: ZenBusiness Banking Closure FAQ
Nov 19, 2026 Upcoming	IRS FIRE e-file system retires (last filing day Nov 19) Businesses that e-file 1099s and other information returns through FIRE.	Source: IRS: Filing Information Returns Electronically (FIRE)
Dec 31, 2026 Upcoming	Amazon Ads legacy Sponsored Ads reports retire Amazon advertisers using scheduled legacy Sponsored Ads reports.	Source: Amazon Ads: Campaign analysis with unified reporting, now available
Apr 1, 2027 Upcoming	Exchange Online EWS fully disabled (phased switch-off from Oct 2026) Microsoft 365 admins whose apps, scripts or services still use EWS.	Source: Microsoft Exchange Team Blog: Exchange Online EWS, Your Time is Almost Up

Dates and sources were read on Oct 16, 2026 (OpenAI custom GPTs: Oct 21, 2026; Exchange Online EWS: Oct 22, 2026). Check each official source for the current date.

Passed (kept for reference)

These dates have passed. The pages stay up for reference and say what applies now.

Date	Deadline	Source
Oct 13, 2026 Expired. Passed Oct 13	Office 2021 and Windows 11 24H2 Home/Pro Anyone still on Office 2021 or Windows 11 version 24H2 Home or Pro.	Source: Microsoft Support: End of support for Office 2021
Oct 16, 2026 Expired. Passed Oct 16	Old Whiteboards still stored in Azure Work or school Whiteboard users with boards still in the "Not migrated" section.	Source: Microsoft Support: Migration of Whiteboards from Azure to OneDrive

Optional printable kits on Gumroad:

$9 FIRE→IRIS Switch Checklist (IRS FIRE, Nov 19)

$29 $1M Insurance Readiness Kit (Amazon, Nov 2)

$29 EU Customs Product Data Checker (EU product identifiers, Nov 1)

$39 Plugin Migration Planner (ChatGPT custom GPTs, Dec 11)

$39 EWS Cutover Kit (Exchange Online EWS, Apr 1, 2027)

General guidance, not legal, tax or IT advice. Check each source's own page (the IRS's own pages or the vendors' own help pages) for your case.