I have seen the similar post from dec. 2017. Almost 6 years has gone by and I wonder if this issue has been addressed.
The solution is to set the property to an empty string. The downside is that doesn’t disappear from this particular contact.
Deleting the property will remove it from HubSpot entirely, right?
Hi @HCarlsen 
I’m guessing you’re refering to this December 2017 post?
I haven’t been able to replicate the issue. When I update a Contact property value to a blank string via the API, this update is reflected on the given Contact record.
To your second question, deleting the property itself will effectively “archive” the property. This means it will no longer be visible within the HubSpot UI. However, it is still available (at least for a while) via the API. Based on my own tests, if the property is then re-created/“unarchived”, the property values that existed when the property was deleted/archived are retained.
Which Contact property are you working with? This might help me better understand the issue you’re experiencing.
I hope this proves useful. Please let me know if you have any follow-up questions.
Hi Zack. Thanks for the answer. Yes, I referred to that post. Disclaimer: My question is based on a beginner’s assumptions on how HubSpot is working. I may be wrong… I expect that the actual contact (object) is based on a template (class), and it then would be possible to remove selected properties from the object.
HubSpot is here used as a middle between our main system and a third and the contact is fed with data from both. When these are processed, I would have liked them to disappear from the list of properties (of the current contact). Initially, I tried setting the properties to “null” expecting this would work.
Deleting the properties isn’t the way as far as I understand your answer so we’ll be setting them to empty strings and leave it to the HubSpot users to get the filters working.
Thanks.
Hi @HCarlsen 
Happy to help 
That makes sense. In my opinion, the best solution for your case to “clear” the relevant property value(s) (i.e. set to a blank string).