The price of train tickets will rise and fall based on demand under a trial to be announced later today by Transport Secretary Mark Harper.
Travellers on some London North Eastern Railway (LNER) services will test out the new way of pricing.
The new scheme will work under a demand and supply system, which will see train fares fluctuate depending on how many seats have been filled.
LNER runs between London King's Cross and Scotland via the East Coast Main Line.
Mr Harper will also confirm plans to expand single leg pricing across the entire LNER network - effectively scrapping return tickets.
Single fare will always be half the cost of a return under this scheme, the Department for Transport has said.
For example, an off-peak single between Durham and London currently costs £1 less than a return.
Many one-way fares will be almost halved as a result of the reform, according to the DfT.
LNER, a publicly owned operator, has trialled single-leg pricing on some of its routes since 2020.
The DfT said it will consider rolling out the system across all of Britain's rail network depending on the success of the extended pilot scheme.
It comes as train fares in England will increase by up to 5.9% from March 5.
Delivering the annual George Bradshaw address to rail industry leaders in central London on Tuesday night, Mr Harper is expected to say: "Today I am setting out the Government's long-term vision for the future of our railways.
"The industry's road to recovery after Covid has been tough, with reform badly needed to win back that lost passenger revenue while putting customers first.
"Today's announcement is the latest example of this Government taking bold decisions and getting on with the job.
"Growing the economy is rightly one of the Prime Minister's top five priorities, and the measures I announce today will unleash more competition, innovation and growth in an important sector of our economy."
Labour's shadow transport secretary Louise Haigh said: "Whichever ticket you buy, passengers are paying more for less under the Conservatives' broken rail system.
"Thirteen years of failure has seen fares soar, more services than ever cancelled, while failing operators continue to be handed millions in taxpayers' cash.
"The next Labour Government will put passengers back at the heart of our railways, and build the infrastructure fit for the century ahead, unlocking jobs and growth."
