From Thursday, Viking Line will be charging passengers a surcharge to cover the escalating cost of fuel. The company says the measure is in place until the end of August.
A return trip between Helsinki and Stockholm will incur an additional 5.80 euro charge, while trips to Tallinn from Helsinki, or those turning round in Mariehamn from Helsinki or Turku, will cost 3.80 more per return journey.
One-way trips will cost half as much.
The charges won't be levied on tickets already bought and paid for, but passengers who change their booking — or those who have booked but not yet paid — will have to cough up.
"Fuel prices have risen significantly since Russia attacked Ukraine," said Viking Line's head of sales, Kaj Takolander.
"Lots of sectors are suffering, including maritime transport. We have been forced to implement an exceptional regime because fuel prices have risen a lot more than expected in a short space of time."
Takolander says there's no prospect of a reduction in fuel prices soon. The company's finances have been hit by the pandemic, when traveller numbers collapsed, and the firm says it can't absorb the cost of higher fuel prices.
Viking Line says those shipping aid to Ukraine, refugees and those accompanying them will not have to pay the surcharge.
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