Total gross proven and probable (2P) reserves amounted to 2.9mln barrels oil equivalent, representing a 53% rise from 1.9mln barrels at the same point in 2016.
It comes after 1mln barrels were upgraded from contingent resources, and follows the divestment of some of the group’s assets. Cabot also noted it produced 130,000 barrels from its reserves in the period.
With a 75% working interest in its assets, Cabot’s net 2P reserve equalled 2.2mln barrels.
The reserves are valued (net present value with a 10% discount rate) at US$36mln gross, US$27mln net.
Keith Bush, Cabot chief executive, said: "An increase of over 50 percent in gross reserves and 20 percent in net reserves, having divested 25 percent of the asset, marks great progress for the company in continuing to realise value from the Canadian asset base.
“The movement of reserves up the value chain from Probable to Proven through a small investment of capital indicates the strength and potential of these assets.
He added: “Increasing core value through production and reserves growth is a fundamental component of the company's strategy.
“The results shown by the reserves report now provide a solid value foundation from which the business can continue to grow."