Rollup in Notion lets you pull and calculate data from a related database. When combined with a date property, rollup can show deadlines, count days between dates, or flag overdue items. This article explains how to set up the relation between two databases and configure a rollup that uses a date column. You will learn the exact steps to create rollups that display or compute date values without breaking the source data.
Key Takeaways: How to Use Rollup With Date Property in Notion
- Relation property in the source database: Links each row to a row in the target database where the date property lives
- Rollup property with Date range or Date value: Displays the exact date from the related row
- Rollup with Show original or Count All: Returns the total number of related date entries instead of the date text
What Is a Rollup and Why Use It With a Date Property
A rollup property reads data from a related database and performs a calculation or displays the value. When you have a date property in the target database, rollup can show that date in the source database without copying it manually. This keeps the original date editable only in the target database and prevents data inconsistency.
Rollup works only after you create a relation between two databases. The relation connects a row in the source database to one or more rows in the target database. After the relation is set, you add a rollup property that points to the date property in the target database. The rollup can then show the date as text, count how many related dates exist, or calculate the earliest or latest date among related rows.
Common use cases include displaying a project deadline from a task database, showing a client’s subscription end date from an invoice database, or counting how many events have a date set. Rollup with date property also works for advanced formulas that need date arithmetic, such as days until a deadline.
Prerequisites for Using Rollup With Date Property
Before you create a rollup, you need two databases that can be linked:
- Source database: The database where you want the rollup to appear. Example: a project tracker.
- Target database: The database that already has a date property. Example: a milestone database with a Deadline column.
The target database must have at least one date property. The source database must have a relation property that points to the target database. If the relation does not exist yet, you must create it first. You also need edit access to both databases.
Steps to Create a Rollup That Displays a Date From a Related Database
- Open the source database
Go to the Notion page that contains the database where you want the rollup to appear. This is the database that will show the date from the related table. - Add a relation property to the source database
Click the + button in the last column header of the source database. Select Relation from the property type menu. In the pop-up, choose the target database that contains your date property. Click Create relation. A new column appears in both databases. - Link rows between the two databases
In the source database, click inside the relation cell for a row. Select one or more rows from the target database. Each selected target row becomes a related item. The relation must be filled for the rollup to return a value. - Add a rollup property to the source database
Click the + button in the last column header of the source database. Select Rollup from the property type menu. A configuration panel opens. - Configure the rollup to read the date property
In the Rollup configuration panel, set Relation to the relation property you just created. Set Property to the date property in the target database. Set Calculate to Show original if you want to display the exact date value. Click Done. The rollup column now shows the date from the related row. - Test the rollup with multiple related rows
If a source row links to more than one target row, the rollup shows the first date alphabetically by default. To change this, set Calculate to Earliest date or Latest date to control which date appears.
How to Use Rollup Calculations With Date Properties
The Calculate option in the rollup property offers several functions that work with date values. Each function returns a different result:
- Show original: Displays the date exactly as it appears in the target database. Works best when each source row links to exactly one target row.
- Earliest date: Returns the earliest date among all related rows. Useful for finding the first deadline in a set of milestones.
- Latest date: Returns the latest date among all related rows. Useful for finding the final deadline.
- Count All: Returns the total number of related rows that have any value in the date property. Null dates are not counted.
- Count Values: Returns the total number of related rows that have a date value. Same as Count All for date properties.
- Count Unique Values: Returns the number of distinct date values among related rows. Duplicate dates are counted once.
- Count Empty: Returns the number of related rows where the date property is empty.
- Count Not Empty: Returns the number of related rows where the date property has a value.
- Percent Empty: Returns the percentage of related rows with an empty date property.
- Percent Not Empty: Returns the percentage of related rows with a date value.
Select the appropriate calculation based on what you need. For example, to see how many tasks in a project have a deadline assigned, use Count Not Empty.
Common Mistakes When Using Rollup With Date Property
Rollup Column Shows “No Data” or Is Blank
This happens when the relation property is empty or the date property in the target database has no value. Check that the relation cell in the source row links to at least one target row. Then verify that the target row has a date entered in the date property. If both are filled, the rollup should display the date.
Rollup Shows a Number Instead of a Date
This occurs when the Calculate setting is set to Count All or another counting function instead of Show original, Earliest date, or Latest date. Open the rollup property settings and change the Calculate option to one of the date-specific functions.
Rollup Shows the Wrong Date When Multiple Rows Are Related
When a source row links to multiple target rows, the Show original setting returns the first date in alphabetical order. To get the earliest or latest date, change Calculate to Earliest date or Latest date. If you need to see all related dates, use a linked database view instead of a rollup.
Rollup Does Not Update After Changing the Date in the Target Database
Rollup values update automatically when the source database page is refreshed. If the rollup appears stale, close and reopen the Notion page or refresh the browser. For desktop apps, restart the app. This forces Notion to recalculate the rollup.
Rollup With Date Property: Common Configurations Compared
| Configuration | What It Returns | Best Use Case |
|---|---|---|
| Show original (single relation) | Exact date from the single related row | Displaying a due date from a linked task |
| Earliest date | Earliest date among all related rows | Finding the first deadline in a project |
| Latest date | Latest date among all related rows | Finding the final deadline |
| Count All | Number of related rows with any date value | Counting how many tasks have a deadline |
| Count Empty | Number of related rows with an empty date | Finding tasks missing a deadline |
Each configuration serves a different purpose. Choose the one that matches the information you need to display in the source database.
Rollup with a date property lets you reference dates from related databases without duplicating data. You now know how to set up the relation, configure the rollup, and select the right calculation. Try using the Earliest date function in a project dashboard to show the next deadline across multiple milestones. For advanced date math, combine the rollup with a formula property to calculate days remaining until the rolled-up date.