---
schema_version: "1"
id: 0d5048ef0b563d589dc8ee009a511c138035b098757bb7a8626e4dd7f5ff2cfe
title: ISNULL
collection: admin
version: current
locale: en-us
portal_url: https://docs.salesforce.com/admin/current/en-us/platform/264-0-0/customize_functions_isnull.md
canonical_url: https://help.salesforce.com/s/articleView?id=platform.customize_functions_isnull.htm&release=264.0.0&type=5
source_site: help.salesforce.com
content_type: documentation
content_hash: eeefdfba9b6fcf2ebe7afe44ef6ece4f8c393012c63d42df33e7c9da191e4f53
description: Determines if an expression is null (blank) and returns TRUE if it is. If it contains a value, this function returns FALSE.
products:
  - Salesforce Platform
  - Security
release: "264"
---
# ISNULL

Determines if an expression is null (blank) and returns TRUE if it is. If it contains a value, this function returns FALSE.

## Use

`ISNULL(expression)` and replace expression with the expression you want evaluated.

## Tips

- Text fields are never null, so using this function with a text field always returns false. For example, the formula field `IF(ISNULL(new__c) 1, 0)` is always zero regardless of the value in the New field. For text fields, use the ISBLANK function instead.
- Multi-select picklist fields are never null in s-controls, buttons, and email templates, so using this function with a multi-select picklist field in those contexts always returns false.
- Don't use ISNULL functions in date/time fields. Empty date and date/time fields always return true when referenced in ISNULL functions.
- Don't use ISNULL functions in text and lookup fields. Empty text and lookup fields always return false when referenced in ISNULL functions. Use the ISBLANK function instead.
- Choose **Treat blank fields as blanks** for your formula when referencing a number, percent, or currency field in an ISNULL function. Choosing **Treat blank fields as zeroes** gives blank fields the value of zero so none of them are null.
- Merge fields can be handled as blanks, which can affect the results of components like s-controls because they can call this function.
- When using a validation rule to ensure that a number field contains a specific value, use the ISNULL function to include fields that do not contain any value. For example, to validate that a custom field contains a value of '1', use the following validation rule to display an error if the field is blank or any other number:
    
    ```
    OR(ISNULL(field__c), field__c<>1)
    ```

![Formula Example](https://sf-zdocs-cdn-prod.zoominsoftware.com/tdta-platform-extend_click-264-0-0-production-enus/5f7d9219-b7b1-4552-8891-f1aba9b289fc/images/icon_example.png)

Formula Example

```
(IF(ISNULL(Maint_Amount__c), 0, 1) + ​
 IF(ISNULL(Services_Amount__c), 0,1) + ​
  IF(ISNULL(Discount_Percent__c), 0, 1) + ​
   IF(ISNULL(Amount), 0, 1) +​
    IF(ISNULL(Timeline__c), 0, 1)) / 5
```

This formula takes a group of fields and calculates what percent of them are being used by your personnel. This formula field checks five fields to see if they are blank. If so, a zero is counted for that field. A “1” is counted for any field that contains a value, and this total is divided by five (the number of fields evaluated). This formula requires you to select the **Treat blank fields as blanks** option under Blank Field Handling while the Advanced Formula subtab is showing.

![Validation Rule Example](https://sf-zdocs-cdn-prod.zoominsoftware.com/tdta-platform-extend_click-264-0-0-production-enus/5f7d9219-b7b1-4552-8891-f1aba9b289fc/images/icon_example.png)

Validation Rule Example

```
AND(ISPICKVAL(StageName, "Closed Won"),
  ISNULL(Project_Start_Date__c))
```

This validation rule makes the Project Start Date custom date field conditionally required whenever the stage is Closed Won.