Treasurer Jim Chalmers is clocking it up as a major victory, but his tax package has received a mixed scorecard from the experts.

The federal budget also faces a huge spike in spending if crucial NDIS reforms are delayed past October, which will dwarf the recent tax U-turns.

Treasurer Jim Chalmers is clocking it up as a major victory, but his tax package has received a mixed scorecard from the experts.

The treasurer’s attitude carries a distinct “let them eat cake” arrogance towards the difficult financial realities facing many ordinary taxpayers.