Laughing all the way to the riverbank

Anonymous bidder pays seven-figure sum for toll bridge – but investment could pay for itself within six years

"I don't think I've ever had the pleasure of offering something quite so unusual as this," said auctioneer Duncan Moir with relish as he opened the bidding on lot no 109.

He was referring to Swinford toll bridge in Oxfordshire, which was bought yesterday by an anonymous bidder for a mere £1,080,000. The bridge, which passes over the Thames near the picturesque village of Eynsham in Oxfordshire, dates back to 1767 and is governed by its own Act of Parliament which in effect makes it a tax haven.

A Grade II*-listed structure, it is one of the only toll bridges in Britain to remain in private hands. Its new owner will not have to pay income tax, capital gains tax, inheritance tax or VAT on their new purchase, thanks to an Act passed by King George III which granted private ownership to the Earl of Abingdon.

The bridge, which is in the Witney constituency of the Conservative Party leader David Cameron, is situated in open countryside six miles from the centre of Oxford on the B4044, which links the A40 and the A420. Included in the sale was a two-storey Grade II-listed Cotswold stone cottage beside the bridge, a car park and more than four acres of land comprising part of the riverbank and some woodland.

"It's certainly been the most unusual property I've been involved with," said Charlie Mason of chartered surveyors Humberts Leisure, which facilitated the sale. "It's been a real joy to work with a property that is a little part of British history. It's very quirky and has generated a huge amount of interest through its tax-free status."

The current toll can hardly be called extortionate: motorists using the crossing have to pay 5p if they are in a car, or up to 50p in a lorry. This could be increased by the new owner, but only if they apply through the Department for Transport – something not done since 1994, when the car charge increased from 2p to 5p.

Even if the toll charges remain the same, the bridge could still prove a lucrative investment. Almost 4 million vehicles use it to get in and out of Oxford every year, and long tailbacks often develop during rush hour. The bridge's gross annual income is estimated to be £190,000. At the moment, the charges are collected manually through a toll booth at the bridge's northern end which is unmanned overnight.

But according to Allsop property consultants, which held the auction, the new owner could make an extra £25,000 per year if they install automatic barriers and a pay machine, which would allow them to charge 24 hours a day. Neil Mackilligin, a senior partner at Allsop, said the bridge's new owner was a "private, UK-based individual" who did not live locally and wished to remain anonymous. He will have to pay for maintenance of the bridge, and if he decides to raise the charges he could face the anger of local residents, some of whom claim that the bridge causes unnecessary traffic jams and pollution.

A petition asking for the local council to buy the bridge and scrap the tolls was signed by 770 people, but after the sale a spokesman for Oxfordshire County Council said it "was not financially in a position" to make a bid.

Trevor Johnson, 54, who runs the nearby Talbot Inn, said the bridge was good for business as it provided "a real talking point" for his customers.