The latest cost increases were revealed by the government in an answer to a parliamentary question by Liberal Democrat MP Norman Baker.
The figures showed a cost increase of £1.149bn on seven schemes with the A14 from Ellington to Fen Ditton showing the biggest increase having almost doubled in price from £490M to £944M.
Planned motorway widening schemes are also badly hit by cost increases with M1 J10 to J13 widening is up from £382M to £601M and the M25 J16 to J23 up from £496M to £697M and J27 and J30 upfrom from £402M to £583M.
Roads and climate campaigner at Campaign for Better Transport Rebecca Lush Blum said the figures showed that the government had "secretly rubber stamped" the cost increases.
"The Government's secret rubber-stamping of road costs is inexcusable. Roadbuilding is bad value for money, doesn’t solve our traffic problems and is bad for the environment. The Government should sort out its transport spending, directing more money into the transport schemes that will help us, like public transport."