There are 3 steps in this article section

Login to your account and follow the instruction below.

Step 1. Click on the "Manage Account" located at the bottom of the list on the left hand side of the page.

Step 2. Click on the "Upgrade / Downgrade Subscription" tab and then Click on the "Continue to billing portal" button.

You will be redirected to the Chargebee Customer Portal, as shown below.

In the Payment History Section (5th Section down the page) you will see and Download as PDF link at the right of each invoice.

Step 3. Click on the Download as PDF link to the right of the invoice you desire.

You will then be asked whether you want to open or save the file. Saving it may save time later in case you need it again.