The airtime sales agreement between the two media groups, which has been in place since 2000, has been extended from a rolling five-year term to an eight-year term.
Rob Woodward, chief executive of Glasgow-based STV, said the new agreement would support the group’s “multi-product commercial offering”.
“This simplifies our relationship with ITV and will provide increased efficiency, transparency and stability for the management of our airtime and sponsorship sales in the long term,” said Woodward.
Kelly Williams, ITV’s managing director of commercial, added: “We have a long-standing relationship with STV and we look forward to continuing with our successful partnership.”
In August, STV reported a 50 per cent hike in first-half profits as revenues rose 2.8 per cent.