HBG fell off the monthly top spot, with only £29.7m of work compared with £93.9m last month.
But big orders at Tarmac, including a £78m win for the Scottish National Science Centre in Glasgow, helped lift it from third to first place. Its massive £247.6m work tally also gave it a leg up from fifth to third in the annual league.
Elsewhere, Morrison and John Mowlem came from nowhere to make third and fifth position respectively in the monthly table.
In the architects' league, Building Design Partnership leaped from 12th to fifth place, upping its yearly work won from £159.3m to £246.3m.
And retailer Morrison entered the clients' table at number nine, placing £81.2m of work in the past 12 months.