Three blocks of 800MHz were up for grabs in the 25.1-27.5GHz range and were sold for the starting price.
All three bidders, Telia, Elisa and DNA, which is owned by Telenor, were successful.
Each paid the starting price of €7 million for the new licences which will be valid until the end of 2033.
The Finnish Ministry of Transport and Communications said Elisa won the 25.1-25.9GHz frequencies, Telia got 25.9-26.7GHz and DNA secured 26.7-27.5GHz.
DNA said its newly acquired spectrum in the 26 GHz frequency band will allow for the transfer of larger data amounts than before, making it particularly suitable for high-speed connections in densely populated areas. DNA launched its Home 5G service in December 2019.
Finland allocated the first round of 5G licences in 2018 and 5G services, among the first in Europe, were launched by Telia in October, on the lower 3.5 GHz frequency band.
The next phase of construction resulting from the new licences will begin in July.