We pre-booked ahead and it was £25pp, if you wanted to get access on the day it was £30 and if you were feeling quite well of that it's £100 for "immediate access".
Having previously been up the Empire State Building and Top of The Rock, I have to say that being British this is incredible. You can see for Miles and miles, from the Olympic Stadium in Stratford to the Wembley Arch, all the way to the River Thames snaking around the city.
We did this day as part of a company "strategy/away day", it was great fun and the service was excellent all day. There is also great photo opportunities, again not the cheapest but you do get these in a lovely leather case.
There is also a bar on the 33rd floor I think it is, but a must see for a picture perfect afternoon......even more so if it's a clear bright day.More