London Buses operates a bus from Big Ben to Waterloo Station every 5 minutes. Tickets cost $3 and the journey takes 4 min.
How to get from Big Ben to Waterloo Station
From Big Ben walk to Westminster Underground Station then Tube to Waterloo Underground Station. 1 min £2. From Big Ben walk to Lambeth North, St Thomas' Hospital A&E Department then line 77 bus to Waterloo. 12 min £2. From Big Ben taxi to Waterloo Station. 2 min £6. From Big Ben walk to Waterloo Station. 13 min. From Big Ben walk to Storey's Gate, Westminster then Bikeshare to Waterloo Station 3, Waterloo. 11 min.