Accountsd using lots of CPU constantly [duplicate]

You could try using the Console application to see if accountsd has recorded any errors. Just open Console and enter "accountsd" in the search filter in the top-right corner of the window.

accountsd doesn't just deal with iCloud accounts. It appears to handle all of the accounts listed in the "Internet Accounts" pane of System Preferences. You could try disabling them all, then enabling them one by one to see which one is causing the issue.

In my case, a Gmail account password had changed (I had left a company but wanted to keep checking my mail in case of emergency.)

@Alistair's Console solution sorted me out right away.

The bigger mystery is why a borked account login needs to chew up 100% CPU (???), perhaps someone who works at infinite loop can enlighten us?

Wanders off, muttering to himself something incoherent about Apple developers

Check the console, in my case it showed the following:

23/05/2015 09:43:16.689 icbaccountsd[16967]: SOSCCThisDeviceIsInCircle SOSCCThisDeviceIsInCircle!! 329

I had Google Chrome open with Google+ running and it appears there's something polling related to adding people to circles. Quitting Chrome fixed it. I suspect restarting will fix it only for a while, though.

Date September 29, 2020 Catalina 10.15.7 installed

I had the same problem - noisy fan and very high cpu - 600+ - registered in Activity Monitor. The solution I have found is to disable 'commerce' in the activity window. 'commerce' is just that it seems - everything Apple does to 'smooth' purchases on its platforms. With commerce disabled, my iMac is running fine. Haven't restarted yet though so I imagine it will restart commerce so I'll need to disable it again. Needs an Apple fix.

Up date: I have now restarted and - yay! - so far no return to abnormal over use. 'commerce' is running again, too, as I expected - but all is - so far - fine