The cost of living in Australia sucks right now, but it sucks even more if you're a single parent. Single parents struggle more than two-parent families to put food on the table, and pay for housing, utilities and medical bills, according to the Melbourne Institute research centre.

And if you thought health insurers might be the ones to cut single parents some slack, you'd be wrong. In fact, in extremely shonky behaviour, health insurers seem to be actively pricing single parents right out of the market.

If you're single, it would be cheaper to add a romantic partner to your policy than to add your own child

Take NIB health insurance, for example. If you're a single parent who has Gold Top Hospital ($750 excess) with Basic Extras from NIB, your premiums will double if you want to add a child. But if a couple has the same policy, they'll only pay about an extra 4% to add a child.

In fact, the single-parent policy actually costs more than the equivalent couples policy. In NSW, for example, NIB's Gold Top Hospital cover ($750 excess) with Basic Extras costs $760 for a couple with no kids and $770 for a single parent (monthly before the rebate and any other discounts).

So if you're single, it would be cheaper to add a romantic partner to your policy than to add your own child.

NIB slugs single parents an extra 70% on average to add a child to their insurance, but couples will pay only about 3% extra to take out a family policy. CHOICE health insurance expert Mark Blades says the system should be fairer.

NIB's logic

When asked about their pricing, NIB said: "The cost of a Gold Top single-parent hospital policy is higher than the cost of a policy for a couple reflecting the number of dependants covered. A single parent may have cover for one child, or many. There's no limit. A couple is always two people.

"The price difference reflects the fact more than two dependants could be covered under a single-parent policy. We have a single-parent policyholder in NSW with six children covered. That policyholder pays $763.94 per month.

"A policy for a couple will only ever cover two people – a couple.

"A number of other factors can influence NIB pricing … NIB policies are priced to reflect underlying costs."

So NIB's single-parent policyholders get a better deal the more kids they add to their policy. They'll pay the same premium whether they add one kid or six kids.

But a two-parent family gets the same deal, and they're more likely to take advantage of it. Couples are far more likely than single parents to have more than one kid. Single-parent families most commonly have one dependent child.

if you're a couple and want to add a child to your health insurance, NIB will charge you about an extra 3% to take out a family policy

And single parents will pay a much bigger increase in premium to add those kids than a two-parent family will.

We singled out the worst example of NIB's policies with the Gold Top single-parent hospital policy with $750 excess. But it doesn't get much better across all of NIB's hospital policies. NIB slugs single parents an extra 70% on average to add a child to their health insurance. By comparison, if you're a couple and want to add a child to your health insurance, NIB will charge you about an extra 3% to take out a family policy.

NIB the worst of a bad bunch

NIB isn't the only offender. This is just the worst policy of a bad bunch. Across all insurers, to add a child to your health insurance policy, couples will pay on average an extra 1% in premiums. Sometimes it's up to 10% extra, but in many cases they'll pay nothing extra at all.

Single parents, though, will pay on average an extra 65% to add a child to their policy.

"We think this is unfair. If health insurers add children for free – or for very little – to a couple's policy, they should do the same for a single parent," says CHOICE health insurance expert Mark Blades.

Single parents squeezed out of health insurance

This unfair pricing practice pushes single parents out of the private health insurance market. CHOICE research estimates that only around 31% of single parents have private health insurance, compared to around 57% of couples with children.

Ongoing price increases are making health insurance unaffordable for a lot of struggling Australian households, but private health insurers are marginalising single-parent families the most. Health insurers should charge single-parent families the same per adult as two-parent families for the same policy.

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