3i completed new investments in Magnitude Software and Evernex and made seven bolt-on acquisitions for its portfolio companies in the first half.
"Despite the uncertain macroeconomic environment, the majority of our investments have moved into the second half of the year with decent momentum," Chief Executive Simon Borrows said.
The returns were in line with the same period last year, and 3i's net asset value per share rose 7% to 873 pence on Sept 30, from 815 pence at March 31.
The firm said it would pay an interim dividend of 17.5 pence per share.
(Reporting by Carolyn Cohn, editing by Sinead Cruise)