Increased congestion blamed on changes to traffic lights is costing companies an extra £3.4 million a day, which is being passed directly to customers.
According to the Freight Transport Association (FTA), the cost of delivering goods to London was £16 million a day, but this has soared to more than £20 million a day. Much of the cost is borne by the 95,000 vans operating in the city, which have seen their costs rise from £9.5 million to nearly £12 million a day.
Changes to traffic lights that leave them on green for shorter periods, along with major roadworks to prepare for the road tolls scheme, are being blamed for some journeys increasing from one hour to three.
Every year, the freight industry spends an estimated £880 million annually negotiating the traffic jams.
The shock figures were revealed in a survey of 165 firms, running more than 12,000 vehicles, with one third of firms blaming traffic light phasing for the problems.
Waverley Vintners, a drinks merchants which delivers daily to West End hotels and bars, estimates that phasing of the traffic light sequence has already cost it £5,000, while Simple Simon Foods, which delivers to the Houses of Parliament as well as stores, contract caterers and retail units throughout the capital, has experienced a £2,500 per week loss of business due to missed deliveries.
A spokesman for the FTA said: 'The survey highlighted the problems that companies delivering into London are facing on a day-to-day basis, but the situation looks set to worsen as traffic becomes virtually gridlocked.
'What is even more infuriating for drivers is that traffic light phasing achieves nothing but longer queues and bigger headaches as they have no choice but to drive into central London to serve the shops, restaurants and hotels.
'The extra costs that are being forced on operators because of the delays will inevitably hit Londoners where it hurts – in the pocket.'