Salesforce 4-Digit Year Validation

I had an ask from the business for users to enter a year into a text field for a project I’m working on. The key challenge with using a text field for a 4-digit year value is that users can enter text too (it is a text field after all). This is easily overcome using this REGEX expression for a Salesforce 4-Digit Year validation….

NOT(
    AND(
        REGEX( Year__c, "^([2][0-9][0-9][0-9])$" ),
        ABS( VALUE( Year__c ) - YEAR( TODAY() ) ) < 2
    )
)

The REGEX( Year__c, “^([2][0–9][0–9][0–9])$” ) expression only allows for years greater than or equal to 2000. If you want it to work for 20th century years, change “[2]” to “[1]”.

The second line of the rule checks whether the year entered is within one year from today’s date. This helps when users fat-finger their data entry. Extend that to suit your needs. You could also swap out “TODAY()” for an actual date field. The “ABS()” function makes the result a positive integer no matter which year is earlier so we always get the result we want.

To use the validation rule…

1. Create a new Text field named “Year” limited to 4 characters. The character limit is important for obvious reasons.
2. Create new validation on “Year” field, and paste the formula from above and adjust as necessary.
3. Be sure your validation rule is Active!

The “NOT” wrapping function ensures the test is negative and causes the validation to fire. Whenever I can, I’ll write a positive formula for field validations, and then wrap it in a NOT function to make it false.

What validation rules do you like to use for common problems like these?