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HubSpot Developer Changelog

New Standardization of date formats for HubSpot's Form Submissions API

What’s happening

Starting Tuesday, November 30th, 2022 we will be standardizing the format of dates for form submissions that are submitted through HubSpot’s Form Submission API’s to be in the following format:

date properties:

  • YYYY-MM-DD (ex: May 16 2022 would be 2022-05-16)
  • UTC midnight aligned unix millisecond timestamps (ex: May 16 2022 would be 1652659200000)

datetime properties:

  • YYYY-MM-DDThh:mm:ss.sTZD (ex: 1997-07-16T19:20:30.45+01:00)
  • Unix millisecond timestamps (ex: July 16 1997 7:20:30.45 PM UTC +1 would be 869077230045)

For existing forms, you can continue to use the date format that you've been using. For each HubSpot account, we've set a specific date format based on recent form submissions, so as long as all forms in the account remain consistent with the current format being used, date values will continue to be accepted.

New accounts, or existing accounts that use a new format compared to previous submissions, will receive an error if the date format does not match one of the formats detailed above.

After November 30th, 2022, form submissions via the API with dates that are not properly formatted will receive a 400 error response notifying them they are not in the proper format.

Any form submissions made via HubSpot’s embedded forms or through use of the forms module already adhere to this format.

What APIs does this apply to?

The standardization of the date format applies to all form submissions. This will include all submissions sent to the form submission API endpoints including:

Note: if you are using legacy v2 form submission endpoints, we recommend updating those endpoints to the latest v3 versions.

This will also affect values submitted in HubSpot embedded forms, so if you are manipulating field values in embedded forms, you will also need to use this format when changing the values for date fields.

Discuss this change on our community post located here.