Via Post, the new green mail service developed by Microsoft and Royal Mail, has confirmed it will launch by early December in time for the Christmas post rush.

The innovative new service works by providing customers with a free software download that enables them to send correspondence from a computer to any UK address. The message is encrypted and sent to a dedicated printer near the recipient's address and is then printed and delivered by Royal Mail.

Simon Campbell, chief executive of the new company, said that the distribution model could cut the carbon footprint of a letter by 75 per cent. " It could save 100m litres of petrol from lorries alone," he said. "Cutting out this large part of distribution, especially in air mail, could make us carbon positive, meaning people may even earn carbon credits as a result of using the service."

Campell added that the service will start using eight printing distribution centres nationwide, before growing to 30 within a year. This will ensure that " the maximum a letter will physically travel is 20 miles".

Via Post is currently targeting the markets for billing and direct mail marketing, where it claims cost as well as carbon savings could be enormous, and is talking to several banks and utility companies about the service.

Royal Mail estimates the average cost of a letter to be 80p to £1, including stamp and stationary, according to Campbell, whereas Via Post is 29p all inclusive, saving a company about 75 per cent a letter.

Campell added that Royal Mail will seek to use high-quality recycled stationary for all the letters they print, in an attempt to further bolster the service's green credentials.