Australian to U.K.
Amazing banking system - I remember being shocked that (a) my sort/account number was printed on my debit card (how clever!) and (b) money transfers were almost instant as opposed to 2-3 days.
Being able to take money out of any bank’s cash point without paying fees - in Australia you typically pay for using other bank’s ATMs.
Paying for small items on card and being able to split a bill across many cards in a restaurant (Australian restaurants will only take one card per bill).
Drinking on a week night - I was mildly shocked the first time a beer on a Monday night was suggested. Also, having a pint at lunch is totally OK. Buying rounds - I’m still not quite at ease with it.
Whole shops devoted to pre-made sandwiches. The wide range of ready meals in supermarkets. How cheap food is, both eating out and supermarkets. Being readily able to buy fruit and vegetables out of season. The terrible flavour of said fruit and vegetables.
Late opening and early closing of shops on a Sunday, incredibly annoying.
How late the day starts and ends - my parents catch a 6.05am train to work, my last Australian job had an official start time of 8am. Gym classes are offered at 7am on Saturday and Sunday. In London, nothing is open before 9am on weekends, the streets are dead. People start work late and finish late.
The NHS. It’s really not that good, in fact it’s pretty bad. Four weeks wait for a GP apppintment is ridiculous. I once flew back to Australia with untreated pneumonia because I wasn’t sick enough for A&E and couldn’t get a GP appt before I left. I arrived Saturday night and my Dad arranged a GP appt for 9am Monday.
Weddings that go on alll day with tiered guest lists. Having to pay for your own drinks, Australian weddings offer all guests beer and wine for free. Having only a choice of a church or registrar wedding rather than using a celebrant.