> Documentation index: [Saleor](/llms.txt) · [This section](/developer/llms.txt)
> Source: https://docs.saleor.io/developer/bulks/bulk-stock

# Bulk Stock Update

This guide describes mutation allowing users to update stock quantities for multiple product variants in Saleor. The purpose of these mutation could be to synchronize stock levels with external inventory management systems.

info

To perform bulk operations on stocks, you need the `MANAGE_PRODUCTS` permission.

<a id="error-policy"></a>

## Error Policy

`stockBulkUpdate` mutation accepts [`errorPolicy`](/developer/bulks/error-policy.md) argument, which determines how to handle errors.

<a id="stockbulkupdate"></a>

## `stockBulkUpdate`

Mutation [`stockBulkUpdate`](/api-reference/products/mutations/stock-bulk-update.md) allows to update stock quantities for multiple variants in a single operation. This is particularly useful when you need to:

-   Synchronize stock levels with external systems
-   Update stock quantities in bulk
-   Manage stock across multiple warehouses

<a id="example-mutation"></a>

### Example Mutation

**Mutation**

```graphql
mutation StockBulkUpdate($stocks: [StockBulkUpdateInput!]!, $errorPolicy: ErrorPolicyEnum) {
  stockBulkUpdate(stocks: $stocks, errorPolicy: $errorPolicy) {
    count
    results {
      errors {
        field
        code
        message
      }
      stock {
        id
        quantity
        warehouse {
          id
          name
        }
      }
    }
  }
}
```

**Variables**

```json
{
  "errorPolicy": "REJECT_FAILED_ROWS",
  "stocks": [{
    "variantId": "UHJvZHVjdFZhcmlhbnQ6NDE4",
    "warehouseId": "V2FyZWhvdXNlOmIxN2NiMTljLTk4YWEtNGVjOC04YzgzLWFhYTBlZjRjMzMxMA==",
    "quantity": 100
  },
  {
    "variantId": "UHJvZHVjdFZhcmlhbnQ6NDI4",
    "warehouseId": "V2FyZWhvdXNlOmIxN2NiMTljLTk4YWEtNGVjOC04YzgzLWFhYTBlZjRjMzMxMA==",
    "quantity": 100
  }]
}
```

<a id="input-details"></a>

### Input details

For detailed information about all available fields, see the [`StockBulkUpdateInput`](/api-reference/products/inputs/stock-bulk-update-input.md).

**Bulk Stock update fields:**

-   `variantId` or `variantExternalReference` of the product variant to update
-   `warehouseId` or `warehouseExternalReference` of the warehouse where the stock is located
-   `quantity`: New stock quantity

<a id="error-handling"></a>

### Error handling

Each stock in the bulk operation can have its own set of errors. These errors appear in `results[].errors` array and are specific to individual stock updates.

Common error scenarios include:

-   `NOT_FOUND`: Variant ID doesn't exist or Warehouse not assigned to product variant
-   `INVALID`: Missing required fields variantId or variantExternalReference

<a id="webhooks"></a>

## Webhooks

Bulk operations emit webhook events for each updated stock entry:

-   `stockBulkUpdate`:
    -   `PRODUCT_VARIANT_STOCK_UPDATED`: For each updated stock entry