But from next week, Bridges is expected to get Economic Development from Steven Joyce, who has moved up to take over Finance from Bill English.
Justice Minister Amy Adams may pick up Science and Innovation, and Tertiary Education from Joyce as well as getting an Associate Finance role.
Paula Bennett, the Deputy Prime Minister, is well placed to pick up responsibility for Housing New Zealand Corporation from English, which would sit alongside or merge with the Social Housing portfolio she already holds.
She is expected to hang on to State Services which keeps her connected to the entire public sector, and may acquire responsibility for Social Investment.
Bill English, formerly Deputy Prime Minister, was elected National leader and Prime Minister last week by the National Party caucus following the shock resignation of Prime Minister John Key.
Paul Goldsmith, a minister outside cabinet, is tipped to be promoted to Cabinet and could pick up ACC.
Louise Upston, another minister outside Cabinet may be advanced up.
Among the three backbenchers likely to become new ministers are second term MPs Mark Mitchell, of Rodney electorate, and Alfred Ngaro, a list MP of Cook Islands descent.
Defence Minister Gerry Brownlee who is has been ranked No 3 for the past eight years, faces a move down the pecking order to make way for younger faces.
But he is expected to remain a key player in the 'Kitchen Cabinet' and as Leader of the House.
Bill English has been under backbench pressure to demote Building and Housing Minister Nick Smith.
But English defended Smith's record last week publicly, and with houses prices in Auckland cooling, he is less of a lightning rod for criticism about house-price inflation. He also has a large work-programme underway.
Assuming he remains in Cabinet, Smith could be well placed to pick up local Government from Sam Lotu-Iiga to complement his housing duties.