Chancellor Phillip Hammond is to offer cut price rail travel to people aged between 26 and 30.
They will become eligible for a travel card similar to the existing young person's rail card, which is available to people aged 16-25 and offers a discount of 1/3 on rail fares.
It follows claims that the Conservatives are failing to win over younger or so-called "Millennial" voters, born in the 1980s and 1990s.
In another measure designed to help younger voters, Mr Hammond will announce measures to prevent graduates overpaying on their student loans.
Currently, a flaw in the system means some graduates find payments have been taken automatically from their salary even though the loan has been paid off in full. They then have to request the money back.
It follows the announcement in October that the Government is increasing the threshold at which graduates start to repay their loans from £21,000 to £25,000.
This cuts monthly payments and will reduce the total amount many graduates pay over their lifetime. However, it comes after the threshold was frozen for two years, which had the effect of increasing payments in real terms.
Latest polling from YouGov showed that Labour were three points ahead of the Conervatives, with 43 per cent saying they would back Labour if an election was held tomorrow and 40 per cent supporting the Tories.
However, it showed 54 per cent of voters age 25 to 49 would back Labour, with the Tories on 30 per cent.
And 64 per cent of voters aged 18 to 24 would back Labour, while just 19 per cent would vote Conservative.