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# How to Add and Use Relation Fields in My Notion Database (Main Guide)?

Relation fields in Notion let you connect two databases — like linking a Task to a Project or a Contact to a Company. When used with NoteForms, this powerful feature unlocks dynamic form behavior, such as selecting, creating, or editing related entries all from one interface.

#### 🔗 What is a Relation Field?
A relation field links one Notion database to another, allowing you to display and interact with data across connected sources.
**Example:**
* A “Tasks” database can have a relation field to a “Projects” database, so you can assign each task to a project and retrieve project details in context.

#### 🛠️ How to Add a Relation Field in Notion
1. Open your Notion database (e.g., Tasks).
2. Click **+ Add a Property** and select **Relation**.
3. Link it to another database (e.g., Projects).
4. Choose whether to make it a one-way or two-way connection.
5. Give the field a clear name (like “Project” or “Client”).
Once done, you’ll see the relation field in your database and can use it inside your NoteForms.

#### 🚀 What You Can Do with Relation Fields in NoteForms
Here’s how you can maximize your use of relation fields within your forms:
1. **Show a Dropdown of Related Items**
Display a list of entries from your connected database.
→ *To customize which columns appear in this dropdown, [learn how to configure displayed properties](https://help.noteforms.com/en/article/how-to-configure-which-properties-are-displayed-in-my-relation-field-7c7zjo/?bust=1750355132471).*
2. **Allow Users to Create New Related Entries (Sub-Form)**
Enable users to add a new item in the related database directly from your form.
→ *See: [How to allow creation of new relations in my form (sub-form)](https://help.noteforms.com/en/article/how-to-allow-creation-of-new-relations-in-my-form-sub-form-13mx4f8/?bust=1750354563735)
3. **Allow Users to Edit Existing Related Entries (Sub-Form)**
Users can modify an already-linked item (like updating a contact’s info) directly from the form.
→ *See: [How to allow editing of relations in my form (sub-form)](https://help.noteforms.com/en/article/how-to-allow-editing-of-relations-in-my-form-sub-form-jopm2l/?bust=1750355013846)
4. **Apply Filtering to the Dropdown**
Show only the most relevant options — like available items, active users, or current projects.
→ *See: [How to filter options in my Notion relation input field](https://help.noteforms.com/en/article/how-to-filter-options-in-my-notion-relation-input-field-arqa9v/?bust=1750355243238)

#### ✅ Requirements and Notes:
* Ensure both databases (the main and the related one) are shared with NoteForms.
* The relation field must be properly configured and visible in your Notion workspace.
* For issues with missing relation fields, refer to:
[Where is my relation field/column?](https://help.noteforms.com/en/article/where-is-my-relation-fieldcolumn-vaavxs/)
* ⚠️ **Sub-forms for relation creation and editing only work with forms created after June 18, 2025.**