Connecting Mailchimp
Find your Mailchimp API key, load audiences, and add leads to the right audience with optional tags.
Find your API key
Mailchimp uses long-lived API keys for server integrations. The key includes a datacenter suffix, such as -us12, and LeadToSheet needs the full value.
- 1
Open your Mailchimp account
Click your profile in the bottom-left, then choose Account & billing.
- 2
Go to Extras -> API keys
Open Extras, then API keys. You will see existing keys and the option to create a new one.
- 3
Create and copy the key
Name the key LeadToSheet so you can revoke it later. Copy the full string, including the datacenter after the dash.
Tip
The datacenter suffix matters. Paste the whole key, including the -us## ending.
What LeadToSheet does
- Lists up to 100 audiences during setup so you can choose the right one.
- Adds or updates the contact in the audience you select (upsert via /lists/<id>/members/<emailHash>).
- Populates only the standard FNAME and LNAME merge fields on the Mailchimp contact — custom merge fields like PHONE, COMPANY, or MESSAGE are not currently written, even when LeadToSheet captured those values on the submission.
- Applies optional tags for segmentation.
- Can use Mailchimp double opt-in for new contacts when you enable it in the route (sets status_if_new to 'pending' instead of 'subscribed').
Note
LeadToSheet reads audience names during setup, then writes contacts only to the audience selected for the destination.