Most read story: Government releases eligibility calculator as Families Package kicks in

The Government has released calculators and eligibility guides for major parts of its Families Package that take effect today, hailing it as the biggest boost in household incomes in a decade for thousands of families.

The $5.5 billion Families Package aimed at low and middle income families comes into effect today. Source: 1 NEWS

The Government said from today 384,000 families will be an average of $65 a week better off and $75 by the time the package is fully rolled out in two years.

Click here for links to calculators and information to check your eligibility.

Today sees increases to Working for Families tax credits, including 26,000 more families eligible.

Paid parental leave is extended by four weeks to 22 weeks from today. It'll be extended to 26 weeks from July 2020.

Babies born from today attract a $60 a week Best Start payment, which can continue for three years.

More than 700,000 senior citizens, and 275,000 families get help to warm their homes. A winter energy payment of $450 for single people and $700 for couples, who are beneficiaries or receiving New Zealand Superannuation.

The Government maintains 64,000 children will be lifted out of poverty by 2020.

"We're backing families because this government knows that when families are stronger, New Zealand is stronger," said Finance Minister Grant Robertson.

"From today we're resetting Working for Families so as you earn more, you get to keep more through the tax credits, while thousands more families will become eligible for the scheme," he said.

The Government is also extending the idea of universal super, to a universal winter energy payment for all senior citizens and beneficiaries so cost is no barrier to turning on the heater to keep warm, Mr Robertson said.

Meanwhile, from today Auckland drivers will pay an 11.5-cent-a-litre regional fuel tax which will be used to improve local roads, with more to come.

In October, that will rise to 15 cents a litre as the government introduces a nationwide fuel excise of 3.5 cents a litre, with two similar rises in 2019 and 2020.