The bus is the same.
However, there are exceptional routes in bus companies that can be used,
so you should confirm it in advance.
But basically pasted stickers "PiTaPa" and "ICOCA" or "iC" on the bus that can be used.
If it is not night or strong rainy day, it will be visible easily.http://www9.plala.or.jp/akotetsudo/umegle/umegleIC.JPGhttp://nonamio.weebly.com/uploads/5/8/4/9/58492997/1531817_orig.png
So, PASMO works in "PiTaPa(Non-JR group of railway and bus companies)" and "ICOCA(JR-WEST, railway only)".https://en.wikipedia.org/wiki/ICOCAhttps://en.wikipedia.org/wiki/PiTaPa
Both has not an good English page on the official web,
repost here may faster if using Google translate does not solve.
Card covered area of "PiTaPa" is almost the same as " KANSAI THRU PASS(KTP)",http://www.surutto.com/tickets/kansai_thru_english.html
but not related to whether IC cards(PASMO and more) can be used or not.
If you move a lot, KTP or another passes for sightseeing in both area,
bc only using PASMO will not be a big discount.
It can also be used for shopping at convenience stores and others.https://www.jr-odekake.net/icoca/guide/money/store.html
Re-charging possible at major stations, buses, at most convenience stores in any towns.
Your card's expiration date is "10 years" from the date you last used it.
It will function normally unless it is exposed to strong impact or magnetism.
You can easily find out if you can print card history by train ticket vending machines,
drinnk vending machines and shopping at convenience stores in the airport.https://prtimes.jp/i/1667/5/resize/a42e183c1193cf02a0469dbcde0b8923.JP...