I am planning to visit London in August and wish to see the Parliament building. Is it necessary to take an official tour in order to get in? Everything I see online only mentions taking the tour.
When Parliament is not in session I believe you need to take an official tour to get in. We were there during Easter break and had to take the tour. You can check out http://www.parliament.uk/visiting/; overseas visitors. We had to get our tickets through ticketmaster. Don't usually like official tours but this one was worth it.
I believe that the only way to see Parliament is by taking a tour.
A tour is the only way. You can call, go to the ticket office the day of, or buy through ticketmaster. The ticketmaster site has available dates. http://www.parliament.uk/visiting/visiting-and-tours/summeropening/
In August, as the posters above have said, you can only visit on an official tour. But when the House is sitting you can turn up without having to pay or book and can visit Westminster Hall (the most impressive part of Parliament, in my opinion) and central lobby, and you can join a queue for the viewing gallery to watch a Commons or Lords debate in action.
I thought the only way foreign nationals could enter Parliament was with an organized tour and only on Saturdays? British citizens can enter just about any time with the appropriate ticket/reservation. All the info is on the Parliament website. When we visited in late April from the US, we took the Saturday tour and had our tickets in hand. We really enjoyed the tour and the guide we had was quite knowledgeable and quite good. It's well worth the time and effort to see where American laws had their origins from the Magna Carta in 1215 and throughout British history.