I think that this may best be answered by looking at why a ‘tip’ is called so. In diction, a ‘tip’ in this scenario could also be referred to as a ‘suggestion’ or ‘note’ given as advice. When you leave a tip for your waiter, you are suggesting to them what you thought of the service they provided you with. It has nothing to do with the relative wage of the waiting staff. As a rule of thumb, in a restaurant in the UK I would tip 10% of the final bill for good service. I’m saying to that person, “well done… you are good at what you do, and I was pleased with your service”. At the bottom end of the scale, very poor service would receive no tip whatsoever. The ‘tip’ in this case is, “you obviously don’t care about the customer or your job, and I wouldn’t pay you to piss on me if I was on fire”. I have rarely applied this rule, as I tend to speak up before the bill arrives if I am not happy with the service. I have tipped 100% on the odd occasion, but this was because the food was such good quality & value, and perfect service, that it was warranted. Many restaurants in the UK now have a ‘service charge’ of 15% for a party of 6 or more – still this is not legally binding and you are under no obligation to adhere to this. I’ve worked in restaurants before, and I don’t understand the ‘large party’ service charge. It is less work serving a party of 6 than it is serving 3 tables of 2. It would make more sense in this case to suggest a lower service charge than the normal tip rate, as you spend less time going back and forth between the table and the kitchen. It really varies from culture to culture. In Eastern Europe, a 15% tip will have your waiter dancing in the restaurant for your own amusement (if that’s what floats your boat), whereas in London, anything less than 15% would get you virtually blacklisted at your local eatery. I believe that in some countries you may be required to pay a service charge, but if that ever arrived in the UK, I would simply tell the waiter that I can order & collect my own food from the kitchen, or they can work their arse off for the tip. I would never tip in addition to a mandatory service charge… unless we are talking about Prague - but that’s a different kettle of fish entirely. ;)