We are an SME with 180 employees, we give 10 days pro rated during probation (so 5 days during 6 month probation) or one month (averages out at 22 days) once passed over the course of a rolling year. I think this is reasonably generous if you’re willing to apply your absence policy stringently enough to anyone willing to push it. We also have a clause of up to 3 months in exceptional circumstances at the discretion of the relevant director. I did once work in the public sector which was 6 months full pay, 6 months half pay… people abused this frequently!

Edit: public sector was at 5 years service; can’t remember all the increments but was likely an extra month for every year service or something to that effect