The manufacturer intends to increase prices for contractual magazine buyers by 27-34 (EUR 40-50) per tonne for its coated and uncoated mechanical papers.
It justified the increases, driven by demand and increasing costs, by saying prices had increased by more than 10% in all regions apart from Europe.
A source at UPM said the increase simply reflected the company's resolve to increase profitability.
"This comes after too long a lean period where any reasonable investment to grow has been impossible," said the source.
They added that the rises were "not huge", and hopefully would be seen as "realistic".
The increases are 34 for coated and 27 for supercalendered (SC) and uncoated mechanical papers.
This latest rise follows an earlier increase by UPM in August of 6%-8% for non-contractual and new business.
News of this latest round of price hikes came on the same day that the Finnish paper producer received a record 38.4m fine by the European Commission for its part in a price fixing cartel in the plastic industrial sack sector.
UPM said it will review the decision and consider further measures, but would not elaborate on what these might be.
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