In the universities in the UK, Australia, NZ etc., the salaries of university faculty members increases automatically year-by-year in two ways: 1 to 1.5% increment for inflation correction, and by climbing in the salary level (e.g., lecturer level 5 to level 6, etc.: What is the average salary of assistant professor in New Zealand?). Is the US salary system similar? Say, someone is hired at a university in the US as a tenure-track faculty member. Does this person get some annual salary increase till he\she gets the tenured? Or they have to wait till obtaining the tenure to get some pay raise?
It's a regular job, more or less like any other, and the way raises work is also the same. When there is ample money, people get raises. Sometimes everybody gets the same raise; other times, it's based on merit (or perceived merit, at least). Which was it happens depend on the particular institution, the department, the recent history of raises--pretty much anything.
When you are promoted to a higher professorial rank, there is usually a prescribed step-up in salary. It might be a fixed dollar amount or a percentage--again depending on the institution. This is just like there is a raise associated with getting promoted at any other large employer.
I'll just note that this just my personal experience but, from what I've seen:
- Departments have a formal process for evaluating faculty on the different components of their job, done by a committee of department members and the size of raises will be based on these and other factors (for example, if you have an outside offer, that can trigger a separate negotiation). My understanding is that usually the department chair has final say on these things, but there is also input from higher administration on setting priorities, and the amount of overall money to be distributed. Assistant professors are evaluated with their other colleagues, though their place in their career is taken into account.
- There usually is a large raise associated with promotions like tenure and promotion to full professor. At some places this is formalized with a fixed percentage (say 8%), while at others it is a more informal understanding.
- Getting a raise every year is pretty typical. I've gotten a raise every year since getting my Ph.D. with the exception of one year when I changed jobs. As far as I know, this was true for everybody in my department. My experience is that everybody in the university gets a raise or nobody does, and the latter happens when the university is under pretty serious financial stress (which is, of course, pretty common these days). I have heard tell of places where salaries were frozen for many years, and you could only get a raise through some unusual tactics, such as getting an outside offer. If you wish to find some examples, just google "university salary freeze."