Locating your MailChimp form action URL is pretty simple. You can follow the steps below and if you run into any issues let us know or submit a help request to MailChimp and they’ll help you get the correct URL to use.
Step 1. Log into your MailChimp account and click on the List from the top menu. Create a mailing list for the people to sign up for if you haven’t already.
Step 2. Click on the right down arrow (along with the Stats) of your selected List to see options dropdown.
Step 3. Click on the Signup forms option from the dropdown.
Step 4. Click on the Embedded forms link from the list of form types.
Step 5. Then the Embedded Form code will appear. Look for the action keyword in the form code. This is the Action URL that you are looking for. Copy the action URL from there. Take a look at the screenshot below.