Best known for books, newspapers and travel convenience and founded in the UK in the late 1700s, WHSmith will open a total of four shops at the airport.
Outlets will open for business in Terminal 1 in late 2016 and in Terminal 2 in early 2017.
"It is a pleasure to have yet another international operator arrive in Finland," says Finavia's Elena Stenholm, vice president of commercial services at Helsinki Airport.
"Large global companies are now more interested in Helsinki Airport as a place of business than ever before. This demand and interest shows that we have developed the airport and its commercial services in the right direction for efficiency and profitability."
The three-year contract is worth €25 million, says Finavia.
The WHSmith shops at Helsinki Airport will be operated by SSP Finland, a long-time partner of Finavia.
Finavia has been in close collaboration with both WHSmith and SSP Finland to integrate the look of the new shops with Helsinki Airport and provide a selection to match the needs of customers.
"WHSmith has a long history of international trade and experience in operating at travel hubs," notes Stenholm.
"This expertise, combined with our local know-how, will ensure that the needs of both domestic and international customers will be met. We will monitor the sales of all our shops and constantly adjust the selection based on demand."
According to Marko Alander, general manager of SSP Finland, WHSmith is the perfect retail brand for Helsinki Airport that will significantly improve the convenience offer available to passengers.
WHSmith is a leading retail group in the United Kingdom with operations in 25 countries.
Over half of the company's over 1,300 shops are located in travel environments, such as airports and train stations.