Torridge Bridge, near Bideford, will be closed overnight from 7pm on Sunday 21 October to 6am Monday 22 October.
The planned overnight closure is part of the second phase of the scheme to replace a damaged expansion joint on the bridge. Works are progressing well and the scheme is currentlly on schedule.
A signed diversion will be in place via the Bideford Long Bridge, with a separate diversion in place for HGVs down to Torrington.
The work, which began in September and is expected to last three months, has been carried out at night using temporary two-way traffic lights from 7pm to 6am.
Both lanes of the bridge are open during the daytime with a precautionary 20mph in place at all times.