Originally Posted by YariGuy

In terms of daily usage I think they're pretty much interchangeable. In fact in convenience stores you just say you're using "交通系” (koutsuukei) when making payment (short for 交通系電子マネー , or transport-type e-money).

However, one thing I will say about Suica is that I recently checked my Suica app, and the card I had was gone. Now, I last used it in Feb 2020, but take that as a data point. I don't know how to get it back. Could have happened to Pasmo as well, but I don't know.