Several Polar organizations, one total
In Polar the organization is the boundary for everything — products, orders, analytics and the token itself.
Why you end up with more than one
Polar organizations are cheap to create and scoped to a product line, so people make them freely: one for the main product, one for a side project, one under a personal account from before the company existed, one shared with a co-founder.
That is a sensible way to keep products separate. It also means that the moment you want to know what you earned in total, Polar has no page that can tell you, because every page it has is scoped to one organization.
One token per organization, not one token for all of them
This is the practical difference from every other provider here, and it is worth knowing before you start. A Polar organization access token is bound to the organization that issued it, so connecting five organizations is five trips to five settings screens rather than one.
It is also why a personal access token is not accepted in their place, however convenient that would be: a personal token's reach follows the person's memberships and changes when those change, which is not a stable thing to build five accounts' figures on. The read-only token guide covers what to grant on each one.
Telling six of them apart once they are merged
The problem with a merged view is not producing the total, it is reading it — six bands on one chart are worthless if you cannot tell which is which. Each connected account gets a colour, and that colour follows it into every chart band, table row, chip and total, so a hue on screen means one specific organization and nothing else.
Polar helps here more than the others do. It is one of only two providers that publishes a picture for the organization itself, so a Polar organization arrives already wearing its own logo instead of a generic mark. Colour is never the only signal either — the name is always printed beside it, because a chart that distinguishes accounts by hue alone is unreadable to a good number of people.
Once they are all connected
The accounts selector is a set of tick boxes. All of them ticked is the merged view; two of six narrows every figure on the page to those two. That selection lives in the URL, so a particular slice of your Polar accounts is a link you can send to somebody rather than a set of steps you have to describe.
Adding a different provider later changes nothing about how any of this works. Each one is normalised on the way in, so a total across all 4 of them costs what a total across one costs.
