In second place is family firm B&M McHugh, with international consultant Mott MacDonald in third.
Osborne, which topped the table when it was published last month, is now fourth, although its score remains unchanged.
Some 40 companies are ranked by average delivery score using Network Rail’s PRISM performance improvement tool for all contract worth more than £50,000.
Propping up the bottom of the league table are Colas Rail Morgan Sindall JV and HVMS and, third from bottom, Amey UK.
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