The messages will be shown as part of Clap for Carers.
Highways England is to use its overhead information boards to honour the NHS – with messages inspired by makeshift signs designed by children in Worcestershire.
Messages supporting key workers will be displayed on motorway signage across England between 7.30pm and 8.10pm on Thursday, coinciding with the weekly Clap for Carers tribute.
The move follows the efforts of a community group who erected morale-boosting banners, made in part by school children, on a bridge over the M5 near Worcester last month.
The signs were later taken down due to fears for the safety of road users if the banners had fallen onto the carriageway.
A Highways England spokesperson said: “Everyone at Highways England is incredibly grateful for the everything the NHS, emergency services and others are doing at this difficult time.
“It was fantastic to see children in Worcestershire create their banners to support those on the frontline.
“And while, for safety reasons, we sadly had to take the banners down from a bridge over the M5, on Thursday evening as part of the weekly #Clapforcarers event, we’ll reflect the children’s messages by setting special signage on motorways.”