Palm will produce paper for all of the publisher's dailies and 60 weekly newspaper titles across the country.
Adrian Jeakings, chief executive of Archant, said the move represented a "huge vote of confidence" in the local economy.
He added: "The cultures of the two companies are very closely aligned as both are independent family-owned businesses.
The deal is also good news for the environment and is part of a wider programme of sustainability within Archant."
The newsprint is made from 100% recycled paper and will be manufactured in King's Lynn, just 50 miles away from Archant's Norwich site.
Palm Paper is a subsidiary of Germany-based group Papierfabrik Palm.
Its £400m site, located on Norwich's Saddlebow Industrial Estate, began operation in August last year.
At present, it produces around 400,000 tonnes of the 1.6m tonnes of newsprint used every year in the UK.
Palm Paper to supply Archant with newsprint for newspaper portfolio
Palm Paper has signed a contract to supply all 30,000 tonnes of newsprint used annually by regional newspaper publisher Archant.
