Your custom GPTs need a new home by December 11
OpenAI has scheduled custom GPTs to retire on December 11, 2026, and says the change affects all ChatGPT plans. Enterprise workspaces with an approved deferral have until February 11, 2027.
OpenAI's own path moves each GPT into a ChatGPT plugin. Its FAQ says custom actions, the GPT's selected model and its sharing settings don't carry over, and a migrated personal plugin starts private. Every GPT your team depends on needs rework either way.
If your company already runs on Microsoft 365, do that rework once, in Copilot, next to your files, mail and meetings. Our custom GPT retirement guide has the full checklist.
Source: OpenAI Help Center: Custom GPT retirement and migration FAQ
- Oct 26, 2026Enterprise workspaces: creation of new custom GPTs ended
- Dec 11, 2026Custom GPTs retire
- Feb 11, 2027Retirement for Enterprise workspaces with an approved deferral
Why teams put off switching, and how we handle each worry
Most companies don't stay on two AI tools because they want to. They stay because moving looks like a lot of work. Here is how we take that work off your plate.
"Our people know ChatGPT."
We train on your team's real tasks, showing each one the old way next to the new way, in short sessions by role. Each person sets up their Copilot custom instructions with us.
"Our prompts are scattered everywhere."
We collect the prompts your team relies on, rewrite them for Copilot, and publish them as a shared library in Copilot Prompt Gallery.
"Our custom GPTs run real work."
We rebuild each GPT as a Copilot agent, connect it to the right files, and test it against your team's real prompts before anyone switches.
"Our data is in there."
We export what your ChatGPT plan allows, archive chat history in SharePoint, and move knowledge files into Microsoft 365 with the right permissions.
Why companies are consolidating on Copilot now
Stop paying for two AI tools
Many teams pay for ChatGPT seats on top of Microsoft 365, which includes Copilot Chat at no extra cost on eligible plans. Try the cost calculator to see what you would keep and cut.
Close the data gaps
Every extra AI tool is another place company data goes. Copilot works inside Microsoft 365 and only shows people data they already have permission to see.
Bring shadow AI back inside
Personal ChatGPT accounts used for work sit outside your admin controls and retention policies. Moving that work to a company-managed tool brings it back under them.
Work where your team already is
Copilot agents show up in Copilot Chat and Teams, next to the mail, files and meetings people use every day.
ChatGPT vs Copilot for business
Both are capable assistants. For most companies the difference is where the work happens and who controls the data.
| Topic | ChatGPT Business and Enterprise | Microsoft Copilot (formerly Microsoft 365 Copilot) |
|---|---|---|
| Where people use it | ChatGPT's own web, desktop and mobile apps | Inside Word, Excel, PowerPoint, Outlook and Teams, plus Copilot Chat |
| Company data it can use | Files and apps you upload or connect to it | Your Microsoft 365 mail, files and meetings, within each person's existing permissions |
| Custom assistants | Custom GPTs, retiring December 11, 2026, and plugins | Copilot agents, built in Agent Builder or Copilot Studio |
| Admin and compliance | ChatGPT workspace admin; Compliance Platform on Enterprise and Edu | Microsoft 365 admin center and Microsoft Purview |
| Cost | A separate subscription per seat | Copilot Chat included with Microsoft 365 business plans; the full Microsoft Copilot license is an add-on |
Not every team should move everything. The assessment shows what to move, what to retire, and what, if anything, to keep. See the full Copilot vs ChatGPT comparison.
What moves, and where it lands
Import buttons carry over a few preferences. A real migration moves the whole setup your team depends on and lands it inside Microsoft 365.
| What you have in ChatGPT | Where it lands in Microsoft 365 | Who does the work |
|---|---|---|
| Custom GPTs | Copilot agents, built in Agent Builder or Copilot Studio | We rebuild and test them |
| GPT knowledge files | SharePoint or OneDrive, with the right permissions | We move and secure them |
| GPT actions and connected apps | Copilot Studio connectors and MCP servers | We rebuild and test them |
| Saved prompts | A shared prompt library in Copilot Prompt Gallery | We rewrite them for Copilot |
| Memory and custom instructions | Copilot custom instructions | Each person, in a guided session with us |
| Chat history | Archived in SharePoint, searchable | We export what your plan allows and archive it |
Six steps, nothing lost
Each step has an owner and a sign-off, so nothing quietly breaks along the way.
- AssessWe inventory who uses what: assistants, prompts, files, integrations and spend.
- MapEvery piece gets a home in Microsoft 365, or a reason to retire it.
- RebuildAssistants, connectors and prompt libraries are rebuilt and tested before anyone switches.
- PilotA small group works in the new tool first. We fix what they flag.
- TrainShort sessions built around your team's real tasks, the old way next to the new way.
- Switch overEveryone moves, chat history is archived, and old licenses are retired.
Questions we hear most
When do custom GPTs stop working?
OpenAI has scheduled custom GPTs to retire on December 11, 2026, across all ChatGPT plans. Enterprise workspaces with an approved deferral have until February 11, 2027. Existing conversations with GPTs stay accessible after retirement. See OpenAI's retirement FAQ.
Can we export our custom GPTs?
OpenAI doesn't document a way to export a GPT's configuration or its knowledge files. We work with each GPT's owner to capture its instructions, conversation starters and actions, and collect the original knowledge files, then rebuild it as a Copilot agent.
Can we export our ChatGPT chat history?
It depends on the plan. Free, Plus and Pro users can export their own data. OpenAI says self-service export is not available for Business and Enterprise workspaces; Enterprise and Edu workspaces can use OpenAI's Compliance Platform. We archive whatever your plan allows in SharePoint.
Why not use OpenAI's own migration to plugins?
You can. OpenAI's FAQ says custom actions, the selected model and sharing settings don't carry over, so the GPTs need rework either way. If your company runs on Microsoft 365, rebuilding them as Copilot agents puts them next to your files and people, and removes a separate subscription.
Will Copilot do what ChatGPT does for our team?
We find out before anyone switches. In the pilot we run your team's real prompts through the rebuilt Copilot agents and fix what falls short. The assessment also tells you if anything is better kept where it is.
Does everyone need a paid Copilot license?
Not necessarily. Microsoft Copilot Chat is included at no extra cost with Microsoft 365 business subscriptions, and agents that use only instructions or public websites run on it at no extra cost. Agents that use your SharePoint or other company data are billed by usage. We map which people need the paid Microsoft Copilot license and which don't.
Is Microsoft Copilot the same as Microsoft 365 Copilot?
Yes. Microsoft renamed Microsoft 365 Copilot to Microsoft Copilot, and Microsoft 365 Copilot Chat to Microsoft Copilot Chat. Signed in with a work account, Copilot runs with enterprise data protection; the personal Copilot app is a separate consumer product.
How long does a migration take?
It depends on how many custom GPTs, users and integrations you have, and the timeline comes out of the assessment. Teams facing the December 11 deadline get a plan that rebuilds the GPTs they depend on most first.
Is eMazzanti affiliated with OpenAI?
No. eMazzanti Technologies is an independent IT services company and a Microsoft partner, and offers this service with Messaging Architects. Neither is affiliated with or endorsed by OpenAI.
Who does the work
eMazzanti Technologies is an IT services company and Microsoft partner, and runs AI migrations together with Messaging Architects. A few things we have done before:
Microsoft partner
Named Microsoft's SMB Worldwide Partner of the Year, with Modern Work and Azure specializations.
A New Jersey Best Place to Work
Named one of New Jersey's Best Places to Work for 2026 by NJBIZ, based on a confidential survey of our own team.
We teach Copilot
eMazzanti runs Microsoft Copilot Master Classes for business teams. The training step of every migration comes from the same people.
The migration process was flawless, with zero downtime, and their cost-effective solutions have significantly enhanced our operational efficiency.
There's absolutely no hesitancy for me to recommend eMazzanti to anyone.
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