Björn Arne Christer "Nalle"[1] Wahlroos (born 10 October 1952) is a Finnish banker, investor, and the chairman of the Board in Sampo Group and UPM-Kymmene.

[5][6] His views against government interference and regulation has prompted criticism and controversy throughout the years, especially as despite Wahlroos' wealth, he has collected hundreds of thousands of euros in Finnish agricultural subsidies.

[10] His mother, Marita Wahlroos, is a long-time friend of Martti Ahtisaari, who was a president of Finland (1994–2000) and they both worked in Africa.

Together with half a dozen of his colleagues, Wahlroos bought out the investment banking operations of UBF in 1992 and started the partnership Mandatum [fi] & Co, which soon became the leading advisor of mergers and acquisitions in Scandinavia.

[16] In 2000, Wahlroos merged his banking group into Sampo-Leonia and took over as president and CEO of the combined company, also becoming its biggest private shareholder.

[18][17] In late 2022, Wahlroos transferred the ownership in his main investment companies, worth c. EUR 130 million, to his children, in preparation for his planned retirement from daily business activities.

[22] "Basic security, in my mind, must never be threatened because it is an important part of human modern society", Wahlroos said in the Finnish newspaper Uutispäivä Demari, clearing way to negative income tax thinking.

In March 2010, in an interview in the Image magazine, he spoke of the need to cut Finnish development aid because "we have 50 years of money thrown into a bottomless well".

In addition, he has criticized giving grants to university students because it, according to Wahlroos, "supports idleness", and regards agricultural and forestry research expenditures as excessive.

In 2015, Wahlroos published a book defending his laissez-faire economics viewpoint, De tio sämsta ekonomiska teorierna.