---
title: Relationship Field
label: Relationship
order: 110
desc: The Relationship field provides the ability to relate documents together. Learn how to use Relationship fields, see examples and options.
keywords: relationship, fields, config, configuration, documentation, Content Management System, cms, headless, javascript, node, react, express
---

<Banner >
  The Relationship field is one of the most powerful fields Payload features. It provides for the ability to easily relate documents together.
</Banner>

**Example uses:**

- To add `Product` documents to an `Order` document
- To allow for an `Order` to feature a `placedBy` relationship to either an `Organization` or `User` collection
- To assign `Category` documents to `Post` documents

### Config

| Option           | Description |
| ---------------- | ----------- |
| **`name`** *         | To be used as the property name when stored and retrieved from the database.  |
| **`relationTo`** *   | Provide one or many collection `slug`s to be able to assign relationships to. |
| **`hasMany`**        | Boolean when, if set to `true`, allows this field to have many relations instead of only one. |
| **`maxDepth`**       | Sets a number limit on iterations of related documents to populate when queried. [Depth](/docs/getting-started/concepts#depth) |
| **`label`**          | Used as a field label in the Admin panel and to name the generated GraphQL type. |
| **`unique`**         | Enforce that each entry in the Collection has a unique value for this field. |
| **`validate`**       | Provide a custom validation function that will be executed on both the Admin panel and the backend. [More](/docs/fields/overview#validation) |
| **`index`**          | Build a [MongoDB index](https://docs.mongodb.com/manual/indexes/) for this field to produce faster queries. Set this field to `true` if your users will perform queries on this field's data often. |
| **`saveToJWT`**      | If this field is top-level and nested in a config supporting [Authentication](/docs/authentication/config), include its data in the user JWT. |
| **`hooks`**          | Provide field-based hooks to control logic for this field. [More](/docs/fields/overview#field-level-hooks) |
| **`access`**         | Provide field-based access control to denote what users can see and do with this field's data. [More](/docs/fields/overview#field-level-access-control) |
| **`hidden`**         | Restrict this field's visibility from all APIs entirely. Will still be saved to the database, but will not appear in any API or the Admin panel. |
| **`defaultValue`**   | Provide data to be used for this field's default value. |
| **`localized`**      | Enable localization for this field. Requires [localization to be enabled](/docs/configuration/localization) in the Base config. |
| **`required`**       | Require this field to have a value. |
| **`admin`**          | Admin-specific configuration. See the [default field admin config](/docs/fields/overview#admin-config) for more details. |

*\* An asterisk denotes that a property is required.*

<Banner type="success">
  <strong>Tip:</strong><br/>
  The <a href="/docs/getting-started/concepts#depth">Depth</a> parameter can be used to automatically populate related documents that are returned by the API.
</Banner>

### Example Patterns
Given the variety of options possible for relationships the shape of the data needed for creating and updating collections can vary. When `hasMany` is true, the field data is an array. When `relationTo` is an array, an object with `relationTo` property for the collection slug and `value` for the ID.

<Banner>
  The Payload admin panel will send the correct format of form data needed, the below examples are most useful for understanding Local API operations or saving to the database directly.
</Banner>

#### Has One
The most simple pattern of a relationship is to use `hasMany: false` with a `relationTo` that allows for only one type of collection.
```js
{
  slug: 'example-collection',
  fields: [
    {
      name: 'owner', // required
      type: 'relationship', // required
      relationTo: 'users', // required
      hasMany: false,
    }
  ]
}
```

The shape of the data to save for a document with the field configured this way would be:
```json
  {
    "owner": "6031ac9e1289176380734024"
  }
```

When making a `GET` request to the api, the query params in the URL would be:
`?where[owner][equals]=6031ac9e1289176380734024`.

#### Has One - Polymorphic
Also known as **dynamic references**, in this configuration the `relationTo` field is an array of slugs to tell Payload what the collections to reference are.
```js
{
  slug: 'example-collection',
  fields: [
    {
      name: 'owner', // required
      type: 'relationship', // required
      relationTo: ['users', 'organizations'], // required
      hasMany: false,
    }
  ]
}
```

The shape of the data to save for a document with more than one relationship type would be:
```json
  {
    "owner": {
      "relationTo": "organizations",
      "value": "6031ac9e1289176380734024"
    }
  }
```

When making a `GET` request to the api, note the difference in referencing the `owner.value`:
`?where[owner.value][equals]=6031ac9e1289176380734024`.

You can also query for collections where a field has a relationship to a specific slug: `?where[owners.relationTo][equals]=organizations` which would return only documents that have an owner relationship to organizations.

#### Has Many
The `hasMany` tells Payload that there may be more than one collection saved to the field.
```js
{
  slug: 'example-collection',
  fields: [
    {
      name: 'owners', // required
      type: 'relationship', // required
      relationTo: 'users', // required
      hasMany: true,
    }
  ]
}
```

To save the to `hasMany` relationship field we need to send an array of IDs:
```json
  {
    "owners": [ "6031ac9e1289176380734024", "602c3c327b811235943ee12b" ]
  }
```

When making a `GET` request to the api, the format does not change for arrays:
`?where[owners][equals]=6031ac9e1289176380734024`.

#### Has Many - Polymorphic
```js
{
  slug: 'example-collection',
  fields: [
    {
      name: 'owners', // required
      type: 'relationship', // required
      relationTo: ['users', 'organizations'], // required
      hasMany: true,
      required: true,
    }
  ]
}
```

To save to `hasMany` relationship of more than one kind of collections, use an array of objects having the collection `slug` as the `relationTo` and the related document `id` for the `value`:
```json
{
  "owners": [
    {
      "relationTo": "users",
      "value": "6031ac9e1289176380734024"
    }, {
      "relationTo": "organizations",
      "value": "602c3c327b811235943ee12b"
    }
  ]
}
```

When making a `GET` request to the api, in the same way as the earlier polymorphic:
`?where[owners.value][equals]=6031ac9e1289176380734024`.
