The M1 Northbound between junctions 14 to 15 will be closed from around 10pm on tonight (19/11) until 6am on Monday 22 November.
The closure will allow engineers to lower the motorway surface at Tongwell Lane Farm bridge and adjusting the gradients on the carriageway at Little Linford Lane bridge.
This work is needed because the bridge is currently too low for traffic such as lorries once this section of the M1 becomes a four-lane motorway.
Originally, this stretch of M1 was due to be closed on Friday 22nd October to 6am on Monday 25th October, but was cancelled on the day.
The cancellation came after a collision took place in the earlier hours of the morning that day, however, it is not confirmed if they were linked.
A spokesperson for National Highways said: "As you can imagine, this is a significant piece of work and we have to close the road fully to do it safely. If we are able to complete the work quicker than expected, we will re-open the road and will advise motorists and the public through social media and the electronic signs on the motorway itself.
"During the road closure, drivers will be encouraged to plan ahead and to use alternative routes such as the M40, A1 or the M11 with the A14. We will also ask motorists to avoid this section of the M1 and surrounding roads if possible. Diversion routes will be clearly signed for the duration of this road closure, so please follow the signed diversion routes."
