# How long does Cursor's prompt cache persist before expiring? **URL:** \ **Category:** Discussions\ **Tags:** context\ **Created:** [July 14, 2026, 9:19am UTC](https://forum.cursor.com/t/how-long-does-cursors-prompt-cache-persist-before-expiring/165686 "2026-07-14T09:19:35Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![Oriel\_Gaash](https://avatars.discourse-cdn.com/v4/letter/o/ee7513/32.png) [@Oriel\_Gaash](https://forum.cursor.com/u/Oriel_Gaash)\ **Post date:** [July 14, 2026, 9:19am UTC](https://forum.cursor.com/t/how-long-does-cursors-prompt-cache-persist-before-expiring/165686/1 "2026-07-14T09:19:35Z")
Hi everyone, I’m trying to understand the exact **cache TTL (Time-To-Live)** behavior in Cursor. I know that starting a conversation writes the context to a cache to speed up subsequent prompts and reduce token usage. While standard LLM provider docs (like Anthropic) often list prompt cache persistence at around 5 minutes, my experience in Cursor is different. I often take breaks longer than 5 minutes within a thread, yet the next prompt still feels cached (no heavy delay or full “cache write” cost). **How long does Cursor actually keep the prompt cache alive before it expires?** Is there any background keep-alive happening, or does Cursor’s custom setup persist it longer? ---
**Author:** ![Colin](https://sea3.discourse-cdn.com/cursor1/user_avatar/forum.cursor.com/colin/32/90452_2.png) [@Colin](https://forum.cursor.com/u/Colin)\ **Post date:** [July 14, 2026, 4:11pm UTC](https://forum.cursor.com/t/how-long-does-cursors-prompt-cache-persist-before-expiring/165686/4 "2026-07-14T16:11:11Z")
Hi Oriel! We use the standard caching provided by our providers (that means 5 minutes for Anthropic and 24 hours for most OpenAI models, though [things are changing for GPT 5.6+](https://forum.cursor.com/t/how-long-does-cursors-prompt-cache-persist-before-expiring/165686/6)). We don’t do anything special to keep the cache warm! Also, cache hits can occur between chats (the system prompt rarely changes, for example). That might be part of what feels snappier! ---
**Author:** ![aebp](https://avatars.discourse-cdn.com/v4/letter/a/f19dbf/32.png) [@aebp](https://forum.cursor.com/u/aebp)\ **Post date:** [July 15, 2026, 3:36pm UTC](https://forum.cursor.com/t/how-long-does-cursors-prompt-cache-persist-before-expiring/165686/6 "2026-07-15T15:36:21Z")
Is that also the case for the GPT 5.6 models? In OpenAI’s documentation it seems to be 30 minutes? [Prompt caching | OpenAI API](https://developers.openai.com/api/docs/guides/prompt-caching#prompt-cache-breakpoints) Extended prompt caching (up to 24 hours) doesn’t seem to be available for 5.6 ---
**Author:** ![Colin](https://sea3.discourse-cdn.com/cursor1/user_avatar/forum.cursor.com/colin/32/90452_2.png) [@Colin](https://forum.cursor.com/u/Colin)\ **Post date:** [July 16, 2026, 4:31pm UTC](https://forum.cursor.com/t/how-long-does-cursors-prompt-cache-persist-before-expiring/165686/7 "2026-07-16T16:31:59Z")
You’re right @aebp! We can’t do better than what the model providers allow, so in the case of GPT 5.6 it would be 30 minutes. Updated my previous response. ---
**Author:** ![Oriel\_Gaash](https://avatars.discourse-cdn.com/v4/letter/o/ee7513/32.png) [@Oriel\_Gaash](https://forum.cursor.com/u/Oriel_Gaash)\ **Post date:** [July 21, 2026, 9:22am UTC](https://forum.cursor.com/t/how-long-does-cursors-prompt-cache-persist-before-expiring/165686/8 "2026-07-21T09:22:50Z")
@Colin thanks for the answer. I have to ask. I have an open conversation from about 5 days ago, I went to holiday. continued today that conversation, and after checking in the billing page the corresponding line for my first prompt made today - I have only cache read, without cache write. ![Screenshot 2026-07-21 at 12.21.42](https://us1.discourse-cdn.com/cursor1/original/3X/d/2/d2abfc8096dedb5cfeb8046645679beba32c07d9.png) That confuses me - I would expect the first prompt to have a “massive” cache write, then the next ones to read that cache. What might explain this ? Thanks! ---
**Author:** ![Colin](https://sea3.discourse-cdn.com/cursor1/user_avatar/forum.cursor.com/colin/32/90452_2.png) [@Colin](https://forum.cursor.com/u/Colin)\ **Post date:** [July 21, 2026, 9:25am UTC](https://forum.cursor.com/t/how-long-does-cursors-prompt-cache-persist-before-expiring/165686/9 "2026-07-21T09:25:11Z")
Hey @Oriel_Gaash! Cursor Grok (like Composer) doesn’t charge for cache writes, so they aren’t represented here. ---
**Author:** ![Oriel\_Gaash](https://avatars.discourse-cdn.com/v4/letter/o/ee7513/32.png) [@Oriel\_Gaash](https://forum.cursor.com/u/Oriel_Gaash)\ **Post date:** [July 21, 2026, 1:52pm UTC](https://forum.cursor.com/t/how-long-does-cursors-prompt-cache-persist-before-expiring/165686/10 "2026-07-21T13:52:22Z")
got it, thank you very much! ---
**Author:** ![Steven\_Gu](https://avatars.discourse-cdn.com/v4/letter/s/e79b87/32.png) [@Steven\_Gu](https://forum.cursor.com/u/Steven_Gu)\ **Post date:** [July 29, 2026, 7:35pm UTC](https://forum.cursor.com/t/how-long-does-cursors-prompt-cache-persist-before-expiring/165686/12 "2026-07-29T19:35:07Z")
Hi @Colin, Thanks for clarifying how Cursor handles TTL for Anthropic and OpenAI models! Could you also share what the cache persistence/TTL behavior looks like for **Composer 2.5** and **Grok 4.5** in Cursor? Do they follow standard provider defaults, or is there a specific duration we should expect when taking breaks between prompts? Thanks! ---
**Author:** ![system](https://sea3.discourse-cdn.com/cursor1/user_avatar/forum.cursor.com/system/32/99069_2.png) [@system](https://forum.cursor.com/u/system)\ **Post date:** [October 28, 2026, 10:49am UTC](https://forum.cursor.com/t/how-long-does-cursors-prompt-cache-persist-before-expiring/165686/14 "2026-10-28T10:49:20Z")
Closed on October 28, 2026, 10:49am UTC This topic was automatically closed 90 days after the last reply. New replies are no longer allowed.