Women are being urged to stop relying on the vagaries of "the universe" and start planning for their retirement.
A report last month showed on average, women enrolled in KiwiSaver will end up saving about 29 percent less than men, despite living longer and spending more time in retirement.
Retirement Commissioner Diane Maxwell says research shows women are great at budgeting day-to-day, but aren't so great at setting long-term saving goals.
"I do have a theory – it's because they're too busy," she said on the Paul Henry programme this morning.
"By the time you've done the sandwiches and sorted the kids out and worked and done everything else, when do you get time to sit down and actually plan for your retirement? That might be part of the problem."
She says women are also less likely to educate themselves on money matters, and aren't as willing to take a risk.
"It's partly because they genuinely don't know because they read less about financial products and finance, and it's also because they don't back themselves. They don't take a punt. Men are far more likely to pretend they know and make it up, and women don't."
But what bugs Ms Maxwell the most are women who have taken a leaf out of new age self-help books like The Secret, and think positivity will provide for them in their old age.
"I was talking to a woman who said to me, 'The universe has brought me a buyer for my house.' I said, 'Look, I think the market has brought you a buyer for your house,'" says Ms Maxwell.
"I was talking to another woman who'd left her job. I said, 'What are you doing next?' She said, 'I don't know. The universe is going to lead me to a new job.' And so you get to retirement, and who knows what the universe will provide. It may provide absolutely nothing."
This week is Money Week, and she hopes the publicity will encourage women to sit down with a calculator and figure out what they need to be saving now so they're comfortable in retirement.
"Don't be afraid to talk about it, don't be afraid to read up on it, don't be afraid to learn about it."