Which sentence below is correct?
Ben received a pay rise.
Ben received a pay raise.
In each region you can even use raise / rise without pay and there is no question about what's increased:
Hmmm - just based the general usage of the words in other contexts, I would say "pay rise" denotes some across the board increase that everyone got due to contract negotiations or gov't action. A "pay raise" would denote that Bill alone got the increase.
Even so - it's a stretch and I would normally ask for clarification as the meaning is unclear - I'm not sure anyone else would see the difference. It strikes me as the sort of differentiation that a specialist in accounting or management would make aot the normal guy on the street.