Import Bulk Emails with Headers

What is the best approach to importing ~500K emails to contacts and include the email headers? I can’t seem to find a column that works for email headers with the CSV import process. The API could take several hours to import that many emails.

Hi @justinrea and welcome to the Community, we are so glad to have you here!
Thanks for reaching out to the Community!
I’d like to share these resources for information:
- Imports
- Engagements (email)
I also wanted to invite a couple of subject matter experts to this conversation: Hi @Bortami, @HubSpot_Corey and @Teun have you already succeeded to import email headers into HubSpot to help @justinrea, please? If not, do you have a workaround maybe?
Thanks so much and have a lovely weekend!
Best,
Bérangère

Are you talking about contact email address, 1 on 1 emails sent to contacts, or marketing emails?

If talking sales emails as in the email engagement object, I would do this via the CRM import endpoint. The import endpoint lets you process more data but there is more work to format the JSON file needed. Individual import files are limited to 1,048,576 rows or 512 MB.

“hs_email_header” is the header field you would write to via the API. (Here’s a list of the writable properties)