Top health insurance companies in Australia by market share (2025): memberships, structures, and how to compare value

Why market share is only one part of choosing a health fund

Choosing the right health insurer can feel overwhelming, particularly when you’re weighing up dozens of options and trying to understand what you’re actually getting for your premium. Some people start shopping because they want better value or broader cover. Others are frustrated by out-of-pocket costs and want a policy that better matches how they use healthcare.

Market share can be a useful starting point, because it shows which insurers cover the largest portion of members. But size alone doesn’t guarantee the best value or the best experience. In practice, comparing health insurance works best when you look at eligibility (who can join), the fund’s business structure (for-profit or not-for-profit), and the rules that protect you when you switch policies.

This article explains the main types of health funds in Australia, outlines what “for-profit” and “not-for-profit” can mean for members, and summarises key comparison considerations such as portability and the importance of reviewing your cover regularly. It also includes the leading market share figure available in the extracted material for 2025.

Health insurance premiums: a reminder that prices can change

Health insurance pricing is not static. The extracted information notes that on April 1, 2026, health insurance prices (premiums) are going up by an industry average of 4.41%. While this figure relates to 2026, it underscores a broader point: even if your circumstances don’t change, your premium can. That’s one reason many Australians periodically reassess whether their current policy still represents good value.

The biggest health insurer by market share in 2025 (from the provided data)

Based on the extracted content, Medibank (including its AHM brand) holds the largest market share at 27.1% as of 2025.

This is a significant share of the market, and it helps explain why Medibank and other large brands are often top-of-mind for consumers. However, brand recognition is not the same as suitability. A policy’s value depends on how well it fits your needs, the benefits you can actually claim, and the costs you may still face when you use services.

Open vs restricted membership: who can join which fund?

One of the first distinctions you’ll encounter when comparing Australian private health funds is membership type. The extracted content describes two broad categories: open membership funds and restricted membership funds.

• Open membership funds are available to all Australians who meet residency requirements.
• Restricted membership funds are limited to people connected to certain industries or organisations.

Open funds are the most straightforward option for many households because eligibility is broad. The extracted content lists several large open membership funds as examples, including Medibank, Bupa, HCF and GMHBA.

Restricted funds, by contrast, can only be joined if you meet the relevant criteria. The extracted content gives examples of groups that may be eligible for restricted funds, including teachers, defence personnel, or police employees and their families. If you fall into one of these categories, restricted funds may be worth a closer look, because they can sometimes deliver strong value due to their smaller membership base and not-for-profit structures.

For-profit vs not-for-profit health funds: what’s the difference?

Another major comparison point is the fund’s business structure. The extracted content highlights a common distinction between for-profit and not-for-profit models.

In general terms, a for-profit health fund is run with an objective of generating profit, while a not-for-profit fund is structured differently and may direct more of its financial outcomes back into member benefits and services. The extracted content adds an important nuance: statistically, many not-for-profit funds tend to have higher benefits paid versus premiums collected. They are also described as being seen as capable of delivering better customer satisfaction, and they might even provide better-value extras and hospital cover.

That said, structure alone does not automatically determine whether a particular policy is right for you. The practical takeaway is that it can be helpful to compare what you pay against what you can realistically claim, and to consider how a fund performs on service measures that matter to you.

Don’t assume the biggest brands are always the best fit

Large insurers are often well known, but the extracted content cautions that size doesn’t always correlate with member satisfaction or value. It points to smaller funds that consistently score well in independent customer satisfaction surveys, including Teachers Health, Defence Health, and Westfund.

According to the extracted content, these smaller funds often provide competitive pricing, better extras payouts, and strong hospital agreements with private hospitals. For consumers, the key message is to compare benefits and features directly rather than relying on brand recognition alone.

Portability: switching funds without re-serving waiting periods (in many cases)

Switching health insurance can sound risky, especially if you’re concerned about waiting periods. The extracted content emphasises a “critical rule” built into the Private Health Insurance Act 2007: portability.

Portability is designed to protect consumers and encourage competition between funds. In practical terms, the extracted content states that you don’t have to re-serve waiting periods for benefits you’re already covered for when you switch to a new health fund or policy.

A simple example included in the extracted content illustrates how this works: John switches health funds but has already served his waiting periods for joint replacement surgery on his old policy. In this case, he is immediately covered for that benefit when he switches. The example also describes John being immediately covered for a hip replacement in a private hospital because he had already served his waiting periods for joint replacements on his old policy.

For many people, portability reduces the fear that changing insurers will set them back to “square one.” It also means you can shop around more confidently, focusing on the policy and value rather than feeling locked into your current fund.

Why reviewing your policy every few years can matter

Health funds don’t stand still. The extracted content notes that funds introduce new products and tweak their existing ones every few years. If you’ve been on the same policy for more than two years, there’s a reasonable chance that the market has shifted around you in ways you may not have noticed.

The practical implication is straightforward: comparing your health insurance from time to time can help you avoid overpaying for cover or ending up underinsured. Even if you’re broadly happy with your fund, it can be useful to confirm that your policy still aligns with your needs and that the benefits you value most remain competitive.

How to compare health insurance value beyond market share

The extracted content repeatedly returns to one central idea: compare the benefits, not just the name on the card. While it does not provide a complete checklist of every feature to assess, it does highlight several themes that can guide a value-focused comparison.

• Eligibility and access: Start by confirming whether you can join an open fund or whether you qualify for a restricted fund (for example, through teaching, defence, or policing connections).
• Business structure: Consider whether the fund is not-for-profit or for-profit, noting the extracted point that many not-for-profit funds tend to have higher benefits paid versus premiums collected and may be associated with stronger satisfaction.
• Benefits and out-of-pocket impact: Look closely at what the policy actually pays and where gaps may remain, particularly if out-of-pocket costs have been a pain point.
• Portability protections: Remember that portability rules mean you generally don’t need to re-serve waiting periods for benefits you’re already covered for when you switch.
• Regular reviews: If you’ve been on the same policy for more than two years, consider comparing again, since products and pricing can change over time.

These comparison angles are especially helpful for consumers who feel stuck between wanting better value and not wanting to disrupt their cover. Portability, in particular, is intended to make switching less daunting.

Common questions raised in the extracted content

The extracted material includes several direct, consumer-oriented statements that address frequent concerns. Summarised plainly, they include:

• Are restricted funds only for certain groups? Yes. Restricted funds are only available to certain groups, such as teachers, defence personnel, or police employees and their families.
• Do you have to re-serve waiting periods when you switch? No. Thanks to portability rules, you don’t have to re-serve waiting periods for benefits you’re already covered for.
• Are not-for-profit funds always better? Not always, but many not-for-profit funds offer higher benefit payouts and strong customer satisfaction.

A note on comparison support and industry expertise

The extracted content references Fair Health Care Alliance (FHCA) as a service that can help consumers compare policies line-by-line, describing its advice as expert and unbiased. It also identifies Aaron Savrone as the founder of FHCA and describes him as a health insurance expert with over 15 years of experience. The extracted content states that he launched FHCA in 2017 with an aim of addressing a lack of genuine care in the health insurance comparison space, and that FHCA has received top ratings and awards, including a 5-star Google Review score from hundreds of reviews and being named Best Insurance Comparison Website by ProductReview three years in a row (2023, 2024, 2025).

Whether you use a comparison service or conduct your own research, the underlying principle remains the same: the most useful comparison is one that matches your cover to your needs and checks that you’re not paying for features you don’t use or missing benefits you rely on.

Putting it all together

Australia’s private health insurance market includes both large open funds and smaller restricted options. In 2025, the extracted content indicates that Medibank (including AHM) holds the largest market share at 27.1%. But market share is only one data point. Membership eligibility, the fund’s structure, and the real-world value of benefits and payouts can matter more to your household than a brand’s prominence.

Two practical ideas stand out from the extracted information. First, restricted funds may offer excellent value for eligible Australians, particularly where not-for-profit structures and smaller membership bases support stronger benefits. Second, portability rules under the Private Health Insurance Act 2007 are designed to make switching easier by helping ensure you don’t re-serve waiting periods for benefits you’re already covered for.

With premiums changing over time and funds updating products every few years, a periodic review can be a sensible way to stay confident in what you’re paying for—and what you’ll receive when you claim.