The series of strikes began in October to protest against the right-wing government's planned labour market reforms and proposed cuts to social welfare.

Finland's government, which took office last year, argues that reforms are necessary to boost productivity and cut the country's fiscal deficit.

The Confederation of Finnish Industries (EK) has said the new strikes will cost Finland a preliminary 320 million euros ($350 million) in lost gross domestic product.

The unions have said they are up for a "long fight" if needed and threatened to follow up with more strike action if the government does not back down.

The central organisation of Finnish trade unions, SAK, said major industrial plants and distribution terminals would also be affected.

Here is what companies are expecting:


The Swedish metals maker said the strike in Finland's ports and rail system would affect it negatively, although it will try to limit the impact on customers.

If the strike is carried out as announced, Boliden sees a 300 million Swedish crown ($29 million) hit to its first-quarter profit, of which 100 million crowns would be due to reduced production and 200 million crowns due to delayed deliveries to customers.


Finland's national carrier expects disruptions to its refuelling services.

"We are prepared for disruptions in fuel supply, and aim to minimise the impact on our customers' travel plans," a spokesperson told Reuters.

Preparations include frontloading, refuelling at stations outside Finland and "through-fuelling", the spokesperson added.

The airline's long-haul flights will need additional stop-overs for refuelling that are expected to prolong flight times by around an hour, Finnair told local media.


The Finnish energy company's spokesperson said the strikes would not have a major impact on its operations for now as its power plants are not targeted.


The Finnish oil and biofuels group said the strike could force it to stop production at its Porvoo oil refinery a few days after it starts, cutting off raw material transportation and leading to storage facilities being full.

Porvoo's output was also hit by a two-day strike in January.


The Finnish steel maker cut its first-quarter guidance.

"Assuming the strike will last for 14 days, the negative impact on adjusted EBITDA for Outokumpu is estimated to be approximately EUR 40 million," Outokumpu said.


The Swedish steelmaker said the strike would impact SSAB Europe's first-quarter operating result by some 300 million Swedish crowns.

It will seek to mitigate any impact on customer shipments.


The Finnish forestry firm said the strikes could delay customer deliveries due to the impact on ports and railway transport.

"The strike may in some cases lead to curtailment of production or a temporary shutdown of individual lines or mills," a spokesperson said, adding that could mean extra costs.


Finnish forestry firm UPM said the impacts of the strike vary from one production site to another.

"It is possible that the strike, due to its length, will lead to production stoppages at our plants," UPM said, adding that, at this stage, it was not publicly estimating the financial impact.

UPM said it will explore the possibilities of alternative transport.

($1 = 0.9152 euros)

($1 = 10.2320 Swedish crowns)

(Reporting by Elviira Luoma and Elsa Ohlen, editing by Anne Kauranen and Milla Nissi)