The benefits of Crossrail 2, which will run through London, Surrey and Hertfordshire could be as high as £102bn, according to new estimates by KPMG.
London and the south east is in line for 200,000 new homes and 200,000 jobs as a result of the new network.
Beyond the local benefits, more than £1bn could be added to the West Midlands economy, more than £200m to the north east and as much as £170m to Scotland as a result of the regions' involvement in building it. The new Crossrail would benefit small and medium-sized businesses involved in the supply chain by £5bn.
Where will benefit from estimated supply chain spending?
“This report sets out what Crossrail 2 can deliver, not just for London but for the rest of the south east and the country as a whole," said Michele Dix, managing director for Crossrail 2 at Transport for London, which commissioned the study along with Network Rail.
"This transformative new railway will help drive growth in jobs and housing and add billions of pounds to the UK economy as well as providing much-needed extra rail capacity to meet the needs of our rapidly growing population,” she added.
Read more: Meet the team behind Crossrail 2
Planning for Crossrail 2 is still ongoing with the exact route to be agreed by the end of this year.
Over half of the cost of the project - previously estimated at between £27bn and £32bn - can be covered by local funding, including income from fares, the business rate supplement and the mayoral community infrastructure levy, which helped fund the building of the original Crossrail.
The new estimates on the economic impact of building Crossrail will inform the government's spending intentions in the chancellor's Autumn Statement.