Very simple: through our billing portal, available on https://billing.seats.io.

Note that this uses a different login and password, completely separate from your seats.io account. This login uses the email you gave when you upgraded to a paid subscription. Normally you should have received an invitation email to the portal at that time.

Once you have logged into the portal, you will be presented with a dashboard giving an overview of your billing history, and other details.

Clicking on the "View More" link of the "My Details" panel (highlighted in the image above), you can view and edit your address details.

Clicking on the edit icon (highlighted in the image above), you can change your billing address.

If you don't have access yet, please reach out to support@seats.io, and we'll get you sorted.