The road under Lytham Road railway bridge will remain closed until April 18.
AdvertisementNetwork Rail are carrying out waterproofing and structural repairs.
The road, which cuts through under the railway, has been closed to traffic since Monday February 25.
The work was scheduled to be complete by March 22 but has been delayed until April 18.
Diversions will remain in place.
Read more: Traffic news from Blog Preston
A Network Rail spokesman said: “We’re sorry for the ongoing disruption caused by our bridge repairs at Lytham Road in Preston.
“As the road passes underneath the busy West Coast main line, it had to be closed for this essential maintenance work to take place.
“Due to challenges faced by the contractor during the course of the repairs, the road needs to stay closed until April 18.
“We’d like to apologise for the delay, and we thank road users and residents for their patience while we work hard to finish the project.”
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