If you built a custom GPT and shared its link with clients, students or your team, you've probably seen the banner by now: OpenAI is retiring custom GPTs and asking you to migrate each one to a ChatGPT plugin.
For some GPTs that's a two-minute job. For the ones other people rely on, it isn't, because the thing that made them useful, a link anyone could open, is the part that doesn't come along. Here's what's changing and what to do about it before the deadline.
What OpenAI is changing, and when
OpenAI's custom GPT retirement and migration FAQ schedules custom GPTs to retire on December 11, 2026 (February 11, 2027 for Enterprise workspaces with an approved deferral). After that, they stop running. Your account or workspace notice may show a different timeline, and the dates have changed before, so check yours.
Until then, your existing GPTs keep working, and you can still edit them. Migration doesn't happen on its own: when it's available for your account, you choose Migrate to plugin in My GPTs. Once you migrate a GPT, the original becomes read-only, though it keeps working until retirement. Plugins are the replacement. A plugin bundles skills (written in the same open SKILL.md format many AI tools now use) and connections to other apps and tools.
What moves to a plugin, and what doesn't
When you migrate a GPT, OpenAI carries over the core of it:
Your instructions become a skill inside the plugin.
Your knowledge files are copied into the plugin as reference files.
Connected apps are added to the plugin.
Some things don't make the move:
Sharing. The plugin starts private. Sharing it publicly goes through a separate plugin submission process, and people who used your GPT don't automatically get access.
Your chosen model. The model you picked for the GPT doesn't carry over.
Custom actions. Anything your GPT did by calling another service stops working until you set up a replacement, which may mean building a custom MCP server.
Conversations. Past chats don't move to the plugin. OpenAI says your existing conversations with custom GPTs stay available after retirement.
Who this hits hardest
If you're the only person who uses your GPT, or everyone who uses it is in your ChatGPT workspace, migrating to a plugin is probably all you need.
The gap is for people who shared a GPT by link with people outside their workspace: a consultant who sends clients a diagnostic tool, a teacher who gives a class a study assistant, a trainer whose course runs on a set of GPTs, a small business whose customers open a GPT from its website. For them, the link is the product, and on December 11 it stops working.
Before you migrate: a checklist
Work through this for each GPT that matters, while it still opens.
1. Copy your instructions into a document you control. They're the most valuable part of the GPT.
2. Download your knowledge files and keep them with the instructions.
3. Write down your actions: which services the GPT calls and what each call does, so you know what needs rebuilding.
4. Note your settings: the model you chose, whether web search or image generation is on, and your conversation starters.
5. List everywhere the link lives: your website, course pages, emails, documents, slide decks, QR codes. Each one will need a new link.
6. Decide who needs access after December 11, and whether they're inside your workspace or not. That decides which option below fits.
Your options
Migrate to a ChatGPT plugin. The right choice if you and your workspace are the main users. It keeps everyone in ChatGPT, and OpenAI's migration does most of the work.
Rebuild it in another AI app. Workable if everyone who uses it is on that app too. You'll paste in your instructions and files and recreate your settings by hand.
Bring it to Skillyo and keep a link anyone can open. Paste your GPT's instructions into Skillyo, add its files, and it becomes a skill with a short form and its own link. Anyone you send the link to can open it and run it, without a ChatGPT account. You pick the model for each skill. The same skill also runs inside ChatGPT and Claude, so people who live in ChatGPT can keep using it there, and you can put it on your website or in a Notion page. Conversations and custom actions don't come over here either, so plan for those the same way. See how bringing a custom GPT to Skillyo works.
Replace the old link everywhere it lives
Whichever option you choose, the old GPT link stops working on December 11. Go back to the list from step 5 and swap in the new link, starting with the places your customers, clients or students see most. If you can, tell your regular users ahead of time so a dead link doesn't become a lost customer.
A custom GPT was a way to package what you know so other people could use it. That idea doesn't retire on December 11. If the people you built yours for don't all live in one AI app, [Skillyo](/custom-gpts) keeps it one link away for everyone.