Work to extend the platform at Corby station will start next month.
Network Rail will begin work on the southern end of the platform on Monday, February 4 and will not disrupt passengers or station users.
The extended platform will allow longer trains with more seats to operate between Corby and London St Pancras, providing more comfortable journeys with less crowding.
Jake Kelly, managing director for East Midlands Trains said: “We are pleased to be working with Network Rail to deliver further improvements to the railway around Corby.
“This is all part of the huge programme of investment to improve the Midland Main Line route to London to provide customers with even better journeys.”
The Midland Main Line is undergoing its largest upgrade since it was completed in 1870, which will help to meet the challenge of rising passenger demand and help the growth of regional economies, connecting people to more job, education and leisure opportunities.
Network Rail sponsor, Wendy Bell said: “As a key part of the wider Midland Main Line Upgrade, a significant amount of work has already been carried out to improve the capacity, speed and resilience of the railway in and around Corby.
“This latest work to lengthen the platform at Corby station is an important element in the wider scheme to create a more modern railway capable of meeting future demand.”