The norm is 10 to 12, 5% of the bill. Britons from all over the UK are often seen standing in tidy and orderly queues. Whether it's at the supermarket, at the train station, or at a concert, they'll be waiting their turn at the front. The worst mistake you can make is to skip the lines, that is, to keep going in line.
This will always arouse the disapproval of those who have been waiting patiently. Expedia's travel experts created an interactive guide focused on etiquette around the world, and the United Kingdom is one of the featured countries.