A total of 386 projects are being carried out over the holiday, a period in which rail bosses say "significantly fewer people" travel.
Part of the work, which will affect Great Western Railway, Heathrow Express and TfL Rail services, will enable the engineers to focus on delivering the heavily delayed Crossrail infrastructure.
Major upgrade works are also taking place at London King’s Cross, including tunnel and structure work, drainage inspections and upgrading overhead line equipment.
The majority of this will take place over Christmas Day and Boxing Day - when most of the rail network is traditionally shut down - but there will also be limited trains from the station during the morning of December 27.
Other engineering work means Southeastern Highspeed and Eurostar trains will not stop at Ashford, Kent between December 26 to 29.
Despite the disruption, fewer services have been halted than last year, with 25% fewer engineers working on the network over the Christmas break.
Network Rail chief executive Andrew Haines said: “Our passengers want and deserve a more reliable railway and that’s why this Christmas we are out working on the track and behind the scenes to help make that happen.
"Significantly fewer people travel over the Christmas holidays, which is why we do so much work at this time of year.
"But we know some of our passengers will have important plans, so please check before you travel. We have plenty of people in our stations in the run up to and over the break who are on hand to help."