A long fight by Western Australia to get a fairer GST deal has finally resulted in changes to the system.

Legislation to introduce a floor of 75 cents in the dollar has sailed through federal parliament.

$9 billion in top-up payments will also be made available by the Commonwealth, to ensure no state is worse off.

State Treasurer Ben Wyatt says the extra money will be spent responsibly.

Federal Treasurer Josh Frydenberg joined Gareth Parker to discuss GST reform and small business loans.