# What Is ChatGPT Instant Checkout and How Does It Work?

> What Instant Checkout is, ChatGPT's in-chat payment built on the ACP protocol: how it works, what changed in March 2026 and what it means for your store.

URL: https://clione.ai/glossary/instant-checkout/
Lang: en

Instant Checkout is the name OpenAI gave to ChatGPT's buy button: the one that lets someone finish an order inside the conversation, without opening the store's website. It is not an OpenAI marketplace or a payment gateway of its own, and it is not the same as [ChatGPT Shopping](/glossary/chatgpt-shopping/), the part of ChatGPT that searches for and compares products. It matters to a store because **it is the piece of [agentic commerce](/glossary/agentic-commerce/) that has changed the most in a year**: what you read about it depends on the date it was written.

## How it works

OpenAI introduced it on September 29, 2025. When someone asks a shopping question, ChatGPT shows the most relevant products from across the web, in organic, unsponsored results. If a product supports Instant Checkout, the person taps "Buy", confirms the order, shipping and payment, and **buys without leaving the chat**. The order, the charge and the shipping are handled by the merchant with its usual systems; ChatGPT acts as the user's agent and just passes information between the two. The merchant pays a small fee on each completed purchase; for the user it is free and does not change the price.[^openai-buy]

Under the hood it relies on the [ACP (Agentic Commerce Protocol)](/glossary/acp/), which OpenAI developed with Stripe. The developer documentation asks the store for three flows:[^openai-acp-concepts]

- **The [product feed](/glossary/product-feed/).** A file with the identifiers, descriptions, prices, stock, images and shipping options, validated with a sample and then sent every day.
- **The checkout session.** ChatGPT collects the buyer, shipping and payment details, and calls the store's endpoints to create or update the session. The store validates, calculates the shipping options and taxes, analyzes risk, charges with its provider and **accepts or rejects the order**.
- **The [delegated payment](/glossary/delegated-payments/).** OpenAI prepares a single-use payment request, with a maximum amount and an expiry set according to what the person chose, and passes it to the store's payment provider. OpenAI is not the seller (the _merchant of record_).

The technical specification pins the checkout session down to five endpoints (create, update, complete, cancel and retrieve) and to [webhook](/glossary/webhook/) notices every time the order changes status. The store has to pass conformance tests before it can charge inside ChatGPT.[^openai-checkout-spec]

## What changed in 2026

On March 24, 2026, OpenAI wrote that **the first version of Instant Checkout did not give the flexibility it was after**, so it lets merchants use their own checkout process while it concentrates its effort on product discovery. To anyone who wants a deeper integration it offers building an app inside ChatGPT, as Walmart did.[^openai-discovery] Shopify reflects this in its help: in ChatGPT, the customer finishes the purchase in the store's own _checkout_, opened in a browser inside the app or in a new tab if they use ChatGPT on the web.[^shopify-chatgpt]

Instant Checkout has not gone away. The developer documentation says it is currently available to approved partners, with a form to request access,[^openai-acp-concepts] and the help center says ChatGPT may offer the option on some eligible products and merchants.[^openai-shopping-help] Neither page gives a date for a wider rollout.

On the order of results, OpenAI said in 2025 that having Instant Checkout gave no preference, but that when ranking several merchants selling the same product it counted as one more factor, alongside availability, price, quality and whether the merchant is the primary seller.[^openai-buy] **The current help page lists those factors without mentioning it**, and adds that when the "Instant checkout" label is applied, the cheapest option may be left without the best-price label.[^openai-shopping-help]

## On a store

This is what the first call ChatGPT would make to a **fictional example** coffee maker store would look like, with the structure from the specification: it creates the session with a product and an address, and the store replies with its own calculation. Here it replies that it has no stock left.[^openai-checkout-spec]

```http
POST /checkout_sessions
{
  "items": [{ "id": "MOKA-INOX-6", "quantity": 1 }],
  "fulfillment_address": {
    "name": "Jane Example",
    "line_one": "1234 Chat Road",
    "city": "San Francisco",
    "state": "CA",
    "country": "US",
    "postal_code": "94131"
  }
}
```

```json
{
  "id": "checkout_session_123",
  "status": "not_ready_for_payment",
  "currency": "usd",
  "messages": [
    {
      "type": "error",
      "code": "out_of_stock",
      "path": "$.line_items[0]",
      "content_type": "plain",
      "content": "This product is not available."
    }
  ]
}
```

The full response also carries the order lines, the shipping options, the totals and the links to the store's terms, which is what ChatGPT shows the buyer.[^openai-checkout-spec] What you read in this exchange is who is in charge: **ChatGPT asks and the store decides**. If the inventory the store answers with does not match the feed, the buyer sees an error at the last step. The feed is the part Clione covers: it builds it from the enriched catalog and uploads it every day to the SFTP account OpenAI gives the merchant; whether the products appear and where is up to OpenAI.


That with Instant Checkout OpenAI sells your product and keeps the customer. It is the other way around: in the ACP **OpenAI is not the seller**; the store accepts or rejects the order, charges with its own provider and handles shipping, returns and customer service as it always has.[^openai-acp-concepts][^openai-buy]


## How to check it

1. **Ask ChatGPT a customer's question**, without your brand, and see whether any product shows the option to pay inside the chat or the "Instant checkout" label. Note the date and country.[^openai-shopping-help]
2. **If you sell on Shopify**, remember that in ChatGPT the purchase ends in your own _checkout_, and check that it works well in a mobile browser inside another app.[^shopify-chatgpt]
3. **If you want payment inside ChatGPT**, the route is the request form in the documentation: today it is for approved partners.[^openai-acp-concepts]
4. **Ask your payment provider** whether it supports the ACP's [delegated payments](/glossary/delegated-payments/). If you already charge with Stripe, OpenAI says a single line of code is enough; with another processor, you can adopt the protocol's delegated payment specification without changing provider.[^openai-buy]

## Related concept: agentic checkout

[Agentic checkout](/glossary/agentic-checkout/) is the general concept: an [AI agent](/glossary/ai-agent/) completes the payment on a person's behalf. Instant Checkout is one specific way of doing it, OpenAI's, in which the payment is completed inside ChatGPT and the store charges behind the scenes.[^openai-acp-concepts] In May 2025 Google announced another way for [Google AI Mode](/glossary/google-ai-mode/): you track a product's price, confirm the details and Google **adds the item to the cart on the store's website** and completes the payment with Google Pay, announced for the United States.[^google-shopping-io] The concept is the same; where the payment happens is not.

To keep going, the [ACP (Agentic Commerce Protocol)](/glossary/acp/) explains the protocol underneath and the [agentic commerce reading path](/learn/agentic-commerce/) puts the rest of the pieces in order.