Field 'read_only_value' cannot be modified for property


Using the Companies API, I’m trying to set a custom property to read only within Company but I get the following error.
Field ‘read_only_value’ cannot be modified for property. Can someone explain why the API does not allow for this.

Here is the body that is being sent:

“readOnlyValue”: true,
“type”: “bool”,
“groupName”: “someGroupName”


Hi @jeff.b

The read only setting would mean that the property could only be modified by an internal HubSpot process, which would mean that it could not be modified through the API. We don’t currently have a setting that would prevent a property from being modified in the UI but could still be modified using the API.


@dadams any update on this? IMHO, for most API integrations, changing properties that were set and computed by third-party app has little or no value for user on Hubspot side.


Hi dadams, is this still the case? I too am getting the 'read_only_value' error in Postman for the "hs_email_optout" property. we would like to automate the process of importing the suppression list from our soon to be former ESP on a daily basis. It's, needless to say, a bit tedious. Ironically, we've been able to automate the process (via API) of exporting the suppression list from the other ESP with no problem whatsoever.


Hi @marshre,

Properties set to read only are still only editable via internal HubSpot processes, but if you're trying to update the subscription status of contacts you should instead use the Email API: