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updatedAt: 2026-04-24T19:16:59.000Z
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# Lag time API overview

Lag time is the number of days between when an order is placed and when the item ships. During item setup you can set lag time to 0 or 1 day. Values above 1 day require approval at the item setup category level. Download the Lag Time Exception schema package when you prepare bulk updates. Sellers can:

* **Retrieve lag time for a single item.** Use `GET /v3/lagtime` with a SKU or GTIN. Include a ship node if your catalog uses multiple nodes.
* **Update lag time in bulk.** Submit a feed with `POST /v3/feeds?feedType=lagtime` to change lag time for many items. Use the Lag Time Exception schemas.
* **Validate at scale.** Use feed status to confirm processing, then spot-check items with `GET /v3/lagtime`

## Prerequisites

* A Walmart Marketplace developer account with API access.
* OAuth 2.0 flow in place to request and refresh access tokens. Include the token in `WM_SEC.ACCESS_TOKEN`.
* Required headers on each call: `WM_QOS.CORRELATION_ID`, `WM_SVC.NAME`. `WM_CONSUMER.CHANNEL.TYPE` may be required for some integrations. Refer to the reference pages for any call-specific requirements.

## Endpoints

* **Retrieve lag time**<br />`GET /v3/lagtime` : returns the lag time configured for a SKU or GTIN, optionally scoped by ship node.
* **Update lag time in bulk**<br />`POST /v3/feeds?feedType=lagtime`: submits a feed that updates `fulfillmentLagTime` for multiple items. Use the Lag Time Exception schemas.
* **Check feed status**<br />`GET /v3/feeds/{feedId}`: monitors processing and provides line-level results.

## How it works

### Overall seller journey

1. **Authenticate.** Obtain an OAuth 2.0 access token and send it in `WM_SEC.ACCESS_TOKEN` on every request.
2. **Read current values (optional).** Call `GET /v3/lagtime` to verify the configured lag time before you change it.
3. **Prepare a bulk update.** Build an XML or JSON payload that follows `LagTimeException.zip`, then post it with `feedType=lagtime`.
4. **Monitor processing.** Track your submission with the Feeds APIs until it is processed, then review any line-level errors.

For Marketplace suppliers, the common user journey might entail a seller or solution provider to complete the following flow:

| Scenario                    | Retrieve                                                                                                                                                                                                   | Update                                                                                                                                                            |
| --------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Get Lag time for an item    | To retrieve the lag time for an item by SKU number, call the [lag time](/us-marketplace/reference/getlagtime)  API and specify item SKU code for the `sku` query parameter.                                | To update the lag time for items in bulk, call [POST /v3/feeds/](/us-marketplace/reference/updatelagtimebulk) and set the `feedType` query parameter to \`lagtime |
| Update Lag time for an item | To update the lag time for items in bulk, call POST /v3/feeds and set the `feedType` query parameter to `lagtime`. Include `sku` or `gtin`, optional `shipNode`, and `fulfillmentLagTime` in your payload. | To confirm the change for a single item, call the lag time<br />API and pass the item SKU code in the `sku` query parameter.                                      |

## Best practices

* Keep lag time at 0 or 1 day unless you have an approved exception. This improves delivery speed and customer experience.
* After posting a bulk update, verify processing with the Feeds APIs, then validate a sample of items using `GET /v3/lagtime`.
* Align values with operational reality. Do not set a lag time you cannot meet.

## Payloads and schemas

Bulk updates use the Lag Time Exception schemas. Download `LagTimeException.zip` from the reference page before constructing XML or JSON. Ensure your entries include a product identifier and a `fulfillmentLagTime` value in days.

## Market availability

This overview applies to the U.S. Marketplace. Some rules and approval processes vary by market. If you sell outside the U.S., confirm details on the global reference page for updating lag time.

## Next steps

* Lag time status (GET)
* Update lag time status (POST)
* Feeds overview
* Request lag time exceptions and reports

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