Developing a new API to be consumed by HubSpot


My developers are going to create an API so that we can utilize more of HubSpot’s features and tracking. However, before they do that I am hoping there are some questions someone can answer on the HS development side because this isn’t like a Marketo to HubSpot integration as it is self made.

The questions we need answered are as follows:

Can HubSpot call our werbsite’s “CreateUser” API?

Can HubSpot call that API in real time when a user fills out the registration form in HubSpot?

Can HubSpot call that API repeatedly, multiple times (for the scenario where it is not a self registering user, but rather a file import)?

Can HubSpot populate a drop down in a registration form from a list of values? (for example a list of specialties)

Can HubSpot call an external API (not the website’s API) for validating whether a user’s license number is correct?

If any of this needs further information or clarification please let me know.


Hi @Clinician1

The only system that HubSpot would have to make calls to an external system would be with webhooks, detailed here:

There are webhook triggers for contacts being created, or for properties changing for contacts, but you’d likely need a consumer between the webhooks HubSpot sends and the system that you want to update.

It would be possible to use the Contact Properties API to create or update a property with a list of values, and that property could be used in a field. HubSpot forms and contacts will validate the options for any form submissions or contact updates that include those types of enumerated properties.

It’s not currently possible to have HubSpot validate license numbers, so you’d need to do that in the license system before updating or creating the contact in HubSpot.


So just to clarify, HubSpot cannot call on an existing API that would validate the license or NPI number? We currently use this API on our site to validate. HubSpot cannot call on that same API?


@Clinician1 if you already have a form using that API for validation, you should be able to use that form on a HubSpot page (using an HTML module instead of a form module), though it would likely take some modification to work correctly.

If you’re using a HubSpot form, there would not be a way to add that API call as part of the validation for the HubSpot form, so you’d need to use a custom form and send the data to HubSpot using the Forms API.