# How to trigger workflow only if property was previously empty **URL:** \ **Category:** Lists, Lead Scoring & Workflows\ **Tags:** workflows\ **Created:** [December 2, 2021, 12:53pm UTC](https://community.hubspot.com/t/how-to-trigger-workflow-only-if-property-was-previously-empty/47865 "2021-12-02T12:53:59Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![SteveT6](https://avatars.discourse-cdn.com/v4/letter/s/848f3c/32.png) [@SteveT6](https://community.hubspot.com/u/SteveT6)\ **Post date:** [December 2, 2021, 12:53pm UTC](https://community.hubspot.com/t/how-to-trigger-workflow-only-if-property-was-previously-empty/47865/1 "2021-12-02T12:53:59Z")
Hi, I am looking at how to create a workflow where it is triggered only when a property was previously empty rather than changed to a specific value. There are two ways I have found but I wanted top see if these are correct or if there is a simpler solution I am missing. 1 - Add to workflow when the property is empty then add a if/then branches so if it changes it follows certain routes - this makes every contact in the DB get enrolled and a large proportion will not have the field change 2 - Create a list where if the property is empty contacts are added and then run a trigger of if they are on the list in last (period of time) and the property gets changed to x - this is not tested Any help or best practice direction would be great Thanks Steve ---
**Author:** ![karstenkoehler](https://d10pqhm3lwygmk.cloudfront.net/user_avatar/community.hubspot.com/karstenkoehler/32/68554_2.png) [@karstenkoehler](https://community.hubspot.com/u/karstenkoehler)\ **Post date:** [December 2, 2021, 1:07pm UTC](https://community.hubspot.com/t/how-to-trigger-workflow-only-if-property-was-previously-empty/47865/2 "2021-12-02T13:07:55Z")
Hi @SteveT6, The first option should work, yes, if you use the “Delay until event happens” action in workflows: ![karstenkoehler_0-1638450241385.png](https://d2qpr2jzcazej7.cloudfront.net/original/3X/4/e/4e27d62272ca2e8aa9a478b25d1a21af4a3c96a3.png) I’ve found this to be unreliable at times so I’d recommend testing this option thorougly. Your second proposed solution should also work if this is a static list: Use a first workflow to add new contacts (_Create date_ is known) with an empty field to a static list. The second workflow would then pick up contacts when the field value changes from empty to not empty; the enrollment would be based on membership in that list and the fact that the property value is known. It would them remove them from the list – after enrolling them. (The list cannot be active because as soon as the value would be known, the contact would leave the list.) Personally, I would opt for this second option, simply because it seems more sturdy. Let me know if you have any follow-up questions! ---
**Author:** ![SteveT6](https://avatars.discourse-cdn.com/v4/letter/s/848f3c/32.png) [@SteveT6](https://community.hubspot.com/u/SteveT6)\ **Post date:** [December 3, 2021, 10:24am UTC](https://community.hubspot.com/t/how-to-trigger-workflow-only-if-property-was-previously-empty/47865/3 "2021-12-03T10:24:02Z")
Thanks Karsten - I will opt for the second route. Might be nice simple feature addition ‘property has changed from null’ I understand could add a lot of variables/complexity but presume it is a common situation in workflows. ---
**Author:** ![karstenkoehler](https://d10pqhm3lwygmk.cloudfront.net/user_avatar/community.hubspot.com/karstenkoehler/32/68554_2.png) [@karstenkoehler](https://community.hubspot.com/u/karstenkoehler)\ **Post date:** [December 3, 2021, 10:31am UTC](https://community.hubspot.com/t/how-to-trigger-workflow-only-if-property-was-previously-empty/47865/4 "2021-12-03T10:31:22Z")
Definitely, @SteveT6, I would also find this useful. If you consider this thread closed, you can make it easier for others to find this information by [marking my earlier post as a solution](https://community.hubspot.com/t5/Lists-Lead-Scoring-Workflows/How-to-trigger-workflow-only-if-property-was-previously-empty/m-p/535438/highlight/true#M5881). I’d appreciate it! Have a great day!