The construction of Halls H and G have taken 18 months to complete and boost the venue's capacity by 20%.
The development also included the building of a registration atrium with direct access to the centre's Queen's Suite, Hall D, King's Suite and a new outdoor piazza. Other improvements were made to public areas, with landscaping work carried out along Kings Road, while Hall Q now features a street level entrance and additional car parking capacity has been created.
Angus Houston, director at HIC, said: "It is a very exciting time for HIC and its clients. The investment in HIC's facilities through the creation of the two new halls, and improving its existing spaces will ensure we remain competitive and can cater for all manner for events."
Earlier this year, HIC bolstered its marketing team as part of its strategy to boost business. The centre made a £180m contribution to the local economy during the 2010/11 financial year, hosting around 150 events and attracting more than 290,000 visitors.