The cost of running the London scheme in 2006 was £123 million out of a revenue of £245 million. This is 50% of the revenue leaving £122M to be invested in buses. It has reduced the number of vehicles by 70,000 per day (about 26%). 50-60% of this is due to transfers to public transport and only 20-30% due to skirting around the zone. The remainder to car-sharing, reduced number of journeys, more traveling outside the hours of operation, and increased use of motorbikes and cycles.

Paradoxically the greater the success of the scheme in reducing traffic levels the lower will be its income.

There are always those that complain about taxes but Ken Livingstone the Mayor of London that introduced the scheme was easily re-elected with his majority almost untouched 16 months after its introduction even with the proposal at the time of the election to extend the area of it. It is generally popular and I for one find the centre of London more pleasant to be in.

Initially there were reports of a drop in trade and plans to relocate outside the zone as had been predicted by opponents before its introduction but as time went by these declined and the Fourth Annual Review by Transport for London in 2004 indicated that business activity within the charge zone had been higher in both productivity and profitability and that the charge had a "broadly neutral impact" on the London wide economy.

Pollution levels inside the zone have fallen by 18.6%, 22.4% & 17.3% for nitrogen oxides, particulates and carbon dioxide respectively compared with 12.5% 17.5% and 16.2% outside the zone.

There are now plans to introduce charges scaled according to the pollution level up to £25 per day for the worst polluters down to zero for electric vehicles.

In addition in 2008 over a much wider area of London a low emissions zone will be introduced that will ban trucks and public transport vehicles that do not meet strict European pollution standards with fines of up to £1000 per violation.

Although there has been the predicable protests by some, there have been some traders like The Knightsbridge Association have backed the scheme and even called for it to be more stringent.