Rather than singling out poorer families to receive the government's new Winter Energy Payment, the government is relying on wealthy Kiwis to opt out of the scheme.

The payments were officially announced as part of the government's families package at the Half Year Economic and Fiscal Update on Thursday.

Singles with no dependents will be eligible for $450 a year to help cover their winter heating bills, while couples or singles with dependents will get $700 a year.

All Kiwis on a main benefit, including Superannuation or a Veteran's Pension, will be eligible for the cash payment.

But so will any New Zealander over 65, regardless of their assets, savings or income.

"We wanted to make sure it was as easy to implement and efficient to implement as possible," Finance Minister Grant Robertson said, defending the decision not to means-test.

"If somebody doesn't believe they need it they can opt out."

The total package will cost $1.8 billion a year.

Energy and Resources Minister Megan Woods said 1600 Kiwis died each year because of cold housing in winter, while thousands more ended up in hospital.

"That's not right, and we can do better," she said.

Anybody who leaves the country for more than four weeks over the winter months will be ruled ineligible.

Act leader David Seymour believes the payment should be means tested to stop the wealthy accessing payments they don't need.

"Just like the tertiary education policy this Labour government is turning into a reverse Robin Hood, that taxes everybody and actually gives a lot of benefits to the rich as well as the poor," he said.

But NZ First leader Winston Peters, who is both eligible and considerably wealthy, refused to say he if would opt out.

"I didn't think this was about me," he said.

"I'm encouraging them to keep warm in winter and they're less likely to go to hospital as a consequence of not being warm. You actually save money, it fiscally acts as a saving."

Electricity retailers say the cash payment will give people choices about how best to warm their homes including heating, insulation, curtains or double glazing.