ScotRail and Network Rail were named Partnership of the Year at the National Transport Awards for the £11million scheme, which was originally estimated to cost £28m.
The price fell due to closer working arrangements and the use of pioneering technology.
Steve Montgomery, managing director of ScotRail, said: "This award is a great honour for everyone who has been involved.
"As well as reducing costs and our impact on the environment, this partnership project has also made services on the line more reliable, regular and comfortable for our customers."
David Simpson, Network Rail route managing director for Scotland, said: "Our delivery of the Paisley Canal works in just four months and for less than half the original cost estimate has been rightly recognised throughout the industry as a great example of what can be achieved when Network Rail, train operators and contractors work together to deliver best value."
Transport Minister Keith Brown said he was "delighted", adding: "I congratulate ScotRail and Network Rail on this award, which rightly recognises their hugely successful partnership."