Families with children are set to pocket an average of more than $3000 next financial year - more than $60 per week - according to the latest Treasury analysis.
Across all Australian households, the average tax cut will be more than $2000, or more than $40 per week.
Revamped tax cuts aimed at "middle Australia" and to help those struggling with cost-of-living pressures were cleared by federal parliament earlier this year.
Pushing to pass the legislation in February, Prime Minister Anthony Albanese said it would allow low and middle-income earners to keep more of what they earned.
The amended tax package, skewed toward lower-paid workers, will take effect from July 1.
Australians earning less than $150,000 will get a larger return than was promised under the so-called stage three tax cuts, which were legislated in 2018.
Those earning more than $150,000 will still receive a tax cut but it will be less than originally planned.
Treasurer Jim Chalmers said cost-of-living relief - with a focus on families and middle Australia - would roll out to millions of Australians from Monday week.
"The mums and dads of middle Australia will be among the biggest beneficiaries of our tax cuts and energy rebates," he said in a statement on Saturday.
"Our economic plan is all about helping Australians earn more and keep more of what they earn and that’s why we’re focused on strong and sustainable wages growth and cost-of-living tax cuts which will kick in from 1 July."