The broadcaster said it has secured a £60m facility for five years from Barclays and Santander.
This replaces a £57.5m facility that was provided by the two lenders and Bank of Scotland.
Glasgow-based STV said the facility will provide headroom for its ongoing needs and flexibility to help it pursue its growth strategy.
The group said it will pay a lower interest margin on the new facility than under the old arrangment, without giving details of costs.
George Watt, chief financial officer, said the improved pricing reflected the significant improvement in the net debt levels of the group.
STV cut net debt by 21 % annually in the year to 31 December, to £35.7m.
The company increased pre-tax profits to £15.2m in 2013, from £13.1m in 2012.
Total revenue grew to £112.1m from £102.7m.
In a trading update issued in April, STV said total airtime revenue from January to the end of May was likely to be up around 7% year-on-year.
Chief executive Rob Woodward said then STV sees a number of exciting growth opportunities particularly in its non-broadcast areas.
The company's production arm makes a range of programmes aired by other broadcasters including Antiques Road Trip, Celebrity Antiques Road Trip and Catchphrase.
In March STV confirmed plans to make its first payment to shareholders since 2006. It proposed a 2p per share dividend for 2013.