How ChatGPT project memory works
Every ChatGPT project has a memory setting of its own, and it decides how much of the rest of your account leaks in — and out. Here's what Default and Project-only actually do, how to switch a project you already have, what people report as broken, and the one thing no setting changes: a project only remembers what went into ChatGPT.
If you run several clients — or several anything — through ChatGPT, Projects are the closest it comes to keeping them apart, and the memory setting on each project is what decides how apart. There are two settings. One of them can now be changed after the fact, which most guides written before mid-August 2026 still say is impossible. This page works from OpenAI's own documentation, read on 8 September 2026, and quotes it where the wording matters.
What a ChatGPT project is
OpenAI describes Projects as "smart workspaces that keep everything related to a long-running effort in one place": you group chats together, upload reference files, and add instructions that apply to every chat inside. Projects are available on every plan, free and paid, and you can create as many as you like; the file limit is per project — 5 on Free, 25 on Go and Plus, 40 on Pro, Business, Enterprise and Edu. Project instructions override your global custom instructions inside the project, and a chat you drag in from your main history inherits the project's instructions and files. That is the container. The memory setting governs what else ChatGPT may bring into the container, and what escapes from it.
Default vs Project-only memory, in OpenAI's words
"Projects can use either default memory or project-only memory," the help article says. Here is what each one does, using OpenAI's own descriptions:
| Default memory | Project-only memory | |
|---|---|---|
| Your saved memories / memory summary | Referenced. "If memory for your account is enabled, it remains active across all chats, including chats in your projects." | Not referenced. "Your previously saved memories are not referenced in project chats." |
| Other chats in the same project | Yes. On Plus and Pro, "ChatGPT prioritizes the project chats and files." | Yes. "Chats can reference other conversations within the same project." |
| Chats outside the project, including other projects | Yes on consumer and Business plans, "unless the other project is set to project-only memory." On Enterprise and Edu, no — chats stay contained even on Default. | No. Chats "cannot reference conversations outside the project, such as general ChatGPT conversations or conversations in another project." |
| Can chats outside see this project? | Yes on consumer and Business plans: "These chats can also be referenced by conversations outside the project." | No. "Chats outside the project cannot reference conversations from the project." |
| Does the project feed your account memory? | Yes on consumer and Business plans, whenever account memory is on. On Enterprise and Edu, project chats cannot be referenced from outside the project. | No. "Information from the project is also kept out of memory used in chats outside the project." |
| ChatGPT Work | Available. | "ChatGPT Work is not available in the project." |
Read as a whole: Default is one pot with a project-shaped bias — the project's own chats and files come first, but everything else you have told ChatGPT is still in play. Project-only is a wall in both directions, for chats. Two more details are worth knowing before you rely on either. There is no browsable record of what a project has picked up — OpenAI's FAQ answers "Can I see a list of my project memories?" with a flat "No," and adds that if you want a project to ignore a particular conversation "you'll need to delete that conversation or move it to a different project." And project memory has prerequisites: on every plan except Enterprise, OpenAI says both Reference saved memories and Reference chat history must be enabled in your personal settings; Enterprise users need saved-memory referencing on and Memory enabled for the workspace.
How to set project memory on a new project
"You can select a memory setting when you create a project," OpenAI says. The choice sits in the new-project sheet — at launch it was behind More options, where you changed Memory from Default to Project-only (TechRadar's walkthrough of 26 August 2025 gives exactly that click path) — and it is small enough to miss, so look for it before you start the first chat. Leave it alone and you get Default. There is no account-wide switch: "Each project's memory must be set individually," and each project also respects your personal and workspace memory settings.
How to change the setting on a project you already have
Project-only memory itself is not new — OpenAI's release note introducing it is dated 22 August 2025, and it has said from the start that with the setting on, ChatGPT "won't use your saved memories from outside the project to shape responses" and "won't carry anything from the project into future chats outside of the project." What is new is being able to change your mind. Until August 2026 the setting was fixed at creation; guides from 2025 still warn that "once you set a project to Project-only memory, you can't change it later" and that it "only works on new projects." That was true when written and is not true now. OpenAI's release note of 14 August 2026 reads: "You can now change a project's memory setting after you create it." The steps, as OpenAI lists them:
- Open the project.
- Select the three-dot menu and choose Project settings.
- Under Memory, select Default memory or Project-only memory.
- Select Save.
Three things OpenAI attaches to that. "Changes may take a few hours to take effect," so a switch made at nine may not be visible at ten. The switch to project-only is a clean-up as well as a wall: "information from that project is removed from memory used outside the project," while "the project's chats and files remain in the project and can continue to provide context there." And switching back to Default is less predictable — OpenAI says memory behaviour then "depends on your plan and personal or workspace settings," which is the table above. The change is "available on all ChatGPT plans," and it applies to projects made before project-only memory existed: OpenAI's FAQ answers that question with a plain "Yes."
Shared projects
Sharing a project changes the memory setting for you. "Once a project is shared, project-only memory turns on automatically," and a shared project "cannot be switched to default memory." OpenAI is specific about the boundary: shared projects "do not have access to an individual member's context, custom instructions, or memories outside the project" — so nothing from your own memory summary or your other work reaches your collaborators through it. The lock is one-way and permanent: if the workspace owner later removes every collaborator, "project memory will continue to be project-only" and still cannot be changed to Default. Sharing was originally a Business, Enterprise and Edu feature and is now available to Free, Go, Plus and Pro users globally, on web, iOS and Android. One line worth knowing if client material goes into a shared project: OpenAI says it will train on shared-project data only if every contributor and the owner have "Improve the model for everyone" switched on.
"Project memory not working": what people actually hit
The first four are documented behaviour that reads like a fault. The last one is a pattern of user reports that OpenAI's documentation contradicts and that we could not verify either way.
- Chat-history referencing is off. The most common cause, and a self-inflicted one: if you turned off Reference chat history to stop old conversations bleeding into new ones, you also switched off the mechanism project memory runs on. OpenAI lists that toggle, together with saved-memory referencing, as a prerequisite on all non-Enterprise plans. Business and Enterprise users who cannot see the option at all should check that Memory is enabled for the workspace and Personal memory is on.
- You changed the setting an hour ago. "Changes may take a few hours to take effect." Test tomorrow, not now.
- Work mode vanished. A July 2026 thread on r/ChatGPT asked why Work mode had disappeared inside a project-only project on both iPhone and web. That is documented: "ChatGPT Work is not available in the project" when memory is project-only.
- You are looking for the list. There isn't one. Ask the project a question whose answer sits in an earlier chat; if the wrong chat is steering answers, move it out or delete it. Moving has its own hedge in OpenAI's article: "If you don't see Move to project for a chat, the chat may not be eligible; start a new chat in the project instead."
- Bleed-through — reported by users on Reddit, not documented. A December 2025 r/ChatGPT post titled as a PSA said a brand-new project-only project used a personal detail from outside it in its very first reply. A February 2026 thread, one of the most-upvoted on the topic, described a repeatable test: tell ChatGPT a random string in an ordinary chat, then ask for it inside a project-only project — the poster reported it came back, and suspected the leak depended on chat-history referencing being on. An August 2026 post reported the opposite direction: ordinary chats seeming to pick up content from inside a project-only project. OpenAI's article says the wall holds both ways. If the separation matters to you, run the random-string test yourself before trusting it with anything that must not cross.
What project memory still cannot see
Everything above governs chats and files that are inside ChatGPT. Default or Project-only, a project's memory is assembled from the chats in it, the files you uploaded (up to the per-plan cap), its instructions, and — where you attached one — an app such as Google Drive for search (OpenAI notes that Drive content added inside a project is not synced in advance). What is not in it, under either setting, is anything that never went through ChatGPT: the email thread with the client, the redline that arrived as an attachment, the voice memo you dictated in the car after the meeting, the notes from the meeting itself. Each of those enters a project only when you paste or upload it, one item at a time, and stays current only as long as you keep doing that.
So project-only memory answers one question well: will ChatGPT mix this project with that one? It does not touch the other question: does ChatGPT know what has actually happened on this engagement? For most client work, the honest answer is that most of what happened never passed through a chat window. The project holds your conversations about the engagement. The engagement itself lives in your inbox, your files and your notes. (For the wider picture of what ChatGPT keeps and where it stops, see does ChatGPT remember past conversations?)
The project holds the chats. The engagement lives somewhere else.
That gap is what Equerry is built for. Instead of pasting the client's material into a project, you send it the material itself: CC your Equerry address on the client thread — every later reply lands too — or forward the document that arrived on Tuesday; share the PDF from your phone; dictate a voice memo walking out of the meeting; type a note. Ask later — "what's still open with Acme after Thursday's reply?" — and the answer comes back with a source chip pointing at the exact email or note it came from, so you can see at a glance whose thread it is drawing on. It holds only what you sent it, everything it has remembered is listed where you can read it and delete it, and there is no full-inbox handover: the threads you CC are the threads it knows. Before the call, it briefs you from that record rather than from your chats about it.
Keep using Projects for what they are good at — thinking out loud with ChatGPT inside a fenced-off topic — and use the settings above to control what crosses the fence. For the record of the engagement itself, the shift is to an assistant you hand the source material to, and that shows its source when it answers. The full per-client system, with and without Equerry, is in how to keep track of multiple clients.
Sources, all read on 8 September 2026. OpenAI's help-center articles "Projects in ChatGPT" (article 10169521, whose "Updated" stamp put its last edit in mid-August 2026) and "Memory FAQ" (article 8590148), and the ChatGPT release notes (article 6825453) for the 22 August 2025 and 14 August 2026 entries — read on help.openai.com in a browser session on 8 September 2026; TechRadar, 26 August 2025; the 2025 how-to quoted above on the old "can't change it later" rule is avisainewsletter.substack.com, 29 August 2025. Quoted wording is OpenAI's unless attributed. The r/ChatGPT threads dated 13 December 2025, 24 February 2026, 23 July 2026 and 31 August 2026 are user reports we could not verify against OpenAI's documentation. OpenAI moves and relabels these controls often — treat the labels as a guide and your own project settings as the authority for your account.
Frequently asked questions
What is the difference between Default and Project-only memory in ChatGPT?
With Default memory, chats inside a project draw on your saved memories (or memory summary) and, on consumer and Business plans, on conversations outside the project too — OpenAI's wording is that account memory "remains active across all chats, including chats in your projects." With Project-only memory, a project's chats use only what is inside that project: your saved memories are not referenced, chats outside the project cannot see in, chats inside cannot see out, and information from the project is kept out of the memory used elsewhere. One further difference OpenAI documents: ChatGPT Work is not available in a project set to project-only memory.
How do I change the memory setting on an existing ChatGPT project?
Open the project, select the three-dot menu, choose Project settings, pick Default memory or Project-only memory under Memory, and select Save. This has been possible since OpenAI's release note of 14 August 2026; before that the choice was made at creation and could not be changed. OpenAI says the change "may take a few hours to take effect" and that it is available on all ChatGPT plans. Shared projects are the exception: they use project-only memory and cannot be switched to Default.
Why is my project not remembering earlier chats?
Work through four things. First, the prerequisites: on non-Enterprise plans OpenAI says project memory needs both Reference saved memories and Reference chat history enabled in your personal settings, so if you switched chat-history referencing off to stop old chats bleeding into new ones, you switched project memory off with it (Business and Enterprise users also need Memory enabled for the workspace). Second, timing: a memory-setting change can take a few hours to apply. Third, location: a project-only project can only see chats that are actually inside it — a related chat sitting in your main history is invisible until you move it in (and OpenAI notes that if you don't see Move to project for a chat, "the chat may not be eligible"). Fourth, there is no list to check: OpenAI says project memory "does not show a list of memories like personal memory," so the way to test is to ask the project a question whose answer lives in an earlier chat.
Do shared projects use my personal memory?
No. OpenAI's article is explicit: "Once a project is shared, project-only memory turns on automatically," and shared projects "do not have access to an individual member's context, custom instructions, or memories outside the project." The setting cannot be changed to Default while the project is shared, and OpenAI notes that even after the workspace owner removes every collaborator the project stays project-only. Sharing is now available on Free, Go, Plus and Pro as well as Business, Enterprise and Edu plans.
Does project memory include the files and emails the project is about?
Only what you put into the project. Project memory covers the chats inside the project, the files you uploaded to it (5, 25 or 40 per project depending on plan), its instructions, and any app you attached to it for search. An email thread is not part of a project unless you pasted it into a chat or uploaded it as a file; the memory setting decides what ChatGPT may reference, it does not bring anything in. That is the gap an assistant you can CC on the thread closes: Equerry keeps the emails, PDFs and voice memos you send it and answers with the source attached, so the engagement's own record — not just your chats about it — is what gets remembered.
Last updated 2026-09-08.
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