tkts, originally known as the Half Price Ticket Booth, is located in the Clocktower building on the South Side of Leicester Square. It has been in operation since 1980 and is run by the Society of London Theatre. Nowadays most tickets are only available at up to half price, but purchases from tkts certainly represent huge savings over those bought direct from the theatres themselves. At one time you could only buy from tkts on the day of performance, but now you can purchase some tickets up to seven days in advance. You can also check on their website to see exactly what they are selling on any given day, or just take a journey into London and keep an eye on the boards outside the ticket booth. You'll be given precise information regarding the true price of the tickets and the discounted price available from them. Even if you purchase at full price, you won't be charged a booking fee. In addition, any profits made are ploughed back into the theatre industry, so be sure to visit the Clocktower Building for your theatre tickets. Don't consider buying from any of the other vendors claiming to sell cheap theatre tickets, you won't get the same value for money deal.
In 2008 tkts opened a second branch at Brent Cross. You can only buy from them in person, but they have the advantage of offering a special deal on a different show every month.
tkts is in the Clocktower building in Leicester Square where the nearest tube stations are Leicester Square and Piccadilly Circus. The Brent Cross tkts is on the first floor of the shopping centre, by the information desk. For detailed information on how to reach Brent Cross, consult their website.