UK residents and overseas visitors can enter the Houses of Parliament for free and watch MPs debating in the House of Commons. The public gallery is above the back of the chamber, looking down upon the MPs' heads, so you get a great view of the Front Benches and Speaker's Chair.
All you have to do is queue up outside the Cromwell Green visitor entrance (directly opposite the back end of Westminster Abbey) and tell the steward on the gate that you'd like to sit inside the House of Commons. If he tells you the queue is quite lengthy then tell him you'd like to visit the House of Lords instead. He will then issue you with a card and point you towards the airport-style security.
Once you're past the security guards you will enter the historic Westminster Hall (this is almost worth going for alone!). This medieval hall dates back to 1097 and witnessed the trials of Charles I, Guy Fawkes and Thomas More.
You will then have to wait in St. Stephen's Hall for a place to become available. The number of seats in the public gallery is quite limited so you might have to queue for 30-60 minutes. (Note: The queue for the House of Lords is usually a lot shorter than the Commons.)
Be advised that you will have to leave your camera and bags in the cloakroom before you enter the Chamber. You will also need to fill in a form with your personal details -- so bring a pen.
Important note: The most popular debate is held at 12 noon every Wednesday -- Prime Ministers Questions. But this debate is a bit different to the other ones, because 1) it's only open to UK residents, not tourists, and 2) you must write to your local MP beforehand to request a ticket. If you fancy trying that one then have a read through our Prime Ministers Questions (PMQs) page.
Craig has been to see everything at Parliament -- the debates, the tours, everything! -- and has written a big series of reviews on his blog. Here's his review of the House of Commons. And here's his review of the House of Lords. He has also written a review of Prime Minister's Questions. Feel free to ask him some questions about the House of Commons before you go, if you're worried about the process of getting inside. Or post your own question on the forum. You might also like to read about his tour of Parliament as well.
If you enjoy watching political debates then Craig also recommends a visit to Mayor's Question Time at City Hall, and the Common Council at the medieval Guildhall. Or how about spending a wet and rainy Sunday morning watching speeches at Speakers' Corner?
Got a question? – Talk about this event
Guest – “I remember going to this many years ago, when Tony Blair was still Prime Minister (that's how long ago it was!) and it was very entertaining.I went during Prime Minister's Questions, which was very difficult to get tickets for. I seem to remember that we… more”
More political events · More talks · More free events · More events at Houses of Parliament