How many SIMs can my Pixel 8 have?

I conduct ✨science✨ to see if my Pixel 8 can be subscribed to 3 cell plans at once

I've only ever used a single SIM in my phone at once because I live in a well-covered city, but I was recently on a trip to the Michigan U.P., which is… not well-covered.

My Android phone (a Pixel 8) supports eSIMs, which are just pretend SIMs you download from The Internet™. I've never used one before — the last time I switched phone service, physical SIMs were all the rage.

So that begs the question: if eSIMs are imaginary, how many can my phone have at once? I mean, there's no physical constraint, like the single SIM card tray in my phone. So, how many?

Google's support page says you can have two SIMs: two physical, two eSIM, or one of each. Well, you can't have two physical in a Pixel since they don't have two card slots, but if they did, then you could.

But what happens if I download more?

"I don't think he knows about Third SIM Card, Pip."

So I kept my existing phone plan, bought another to give me extra coverage on the trip, then spent $4 on a third phone plan just to see what would happen.

Me when I spend money just to learn something the docs already explain

Survey says:

I can only have two SIMs active. If I add a third, my phone asks me to deactivate one of the active SIMs. I can switch back and forth between any pair of SIMs I please, and my phone service will stay active for all of them, but I can only use two at a time.

For completeness, of the two that are active, I can choose which is my preference for calls and for SMS. I can pick one to be "it" for mobile data. There's a toggle on the other SIM to "use this network when it has better availability", but based on my time in the U.P., I'm not sure it worked very well. My phone often had no connectivity, even when at least one network showed a bar.

How many total SIMs can the phone hold? I haven't seen any official answer, but over on Mastodon, Alvan thinks it's 1 SIM + 5 eSIMs for his Pixel 7.