Mecaplast is based at Peterlee's North West Industrial Estate and is part of the wider Mecaplast Group.
The company employs a workforce of about 120 and supplies plastic components to the automotive sector both in the UK and overseas.
For the year to 31 December 2015, Mecaplast Peterlee Ltd reported turnover of £19.4m compared to £20.7m the previous 12 months.
Of the 2015 total, £18.7m was income from the UK, which was down from £19.7m, while European sales fell from £944,896 to £694,336. Rest of the world turnover was up from £1,921 to £22,631.
Meanwhile, pre-tax profit dipped from £4.34m to £4.14m.
Despite this, Mecaplast said a "very large" capital investment had filled directors with optimism.
"The management team has started to prepare for further investment – partly renewal and partly increased activity – as the company's goof level of client support attracts further interest from the industry it serves," said the manufacturer.
David Cann, general manager at Mecaplast, told Insider: "We're undergoing a period of significant growth after securing several new contracts and investment at group level.
"We expect to add to our headcount during the next year and are particularly keen to attract talented young people into the business as part of our succession planning programme.
"Overall the picture is very positive for the Peterlee plant." In the strategic report accompanying its results, Mecaplast added that the UK marketplace for automotive plastics "remains very competitive" but remained confident.
"As the contracts awarded in the sector are often for five years or more, the company's mid-term sales book remains positive and indeed the company is already considering investments which could enable it to further increase its level of activity from 2016."