How can i delete "cancelled companies" from my log in screen?

Good morning, @mewowcafe.

Unfortunately, removing these company from the list isn't available in QuickBooks Online. However, the system will automatically delete all inactive or cancelled accounts after a year. This is because we hang onto your data for a year in case you change your mind.  

I'm always happy to pass on this feedback to our development team for future improvements within the QuickBooks Product.

Let me know if I can assist with anything else, I'll be around!