The Guardian - Inflation means project £8bn-£10bn more expensive than 2019 estimate, MPs told. The estimated cost of the HS2 line from London to Birmingham has ballooned to as much as £66bn, the scheme's executive chair has told MPs. Jon Thompson told the transport select committee on Wednesday that the current estimate for the first phase of the line could add between £8bn and £10b to the current top-end estimate of £56.6bn.