Tipping is not so much a part of the culture of the UK as it is in America. However, there are some customary practices if you feel the service was good and you want to show your appreciation.
Most hotel bills include a service charge of about 10-12 percent. Where a service charge is not included in a hotel restaurant, it’s usual to tip 10-15 percent of the bill. For rooms and other hotel services you can leave as much or as little as you choose.
Many restaurant bills include a service charge so check the bill to avoid tipping twice. Where service charge is not included, it is customary to tip 10-15 percent of the bill.
It’s not customary to tip in pubs, bars or for any over-the-counter service.
Taxi drivers generally expect 10-15 percent of the fare.