A pre-existing condition is any illness, injury or symptom you had, or knew about, in the 6 months before joining health insurance. If you have one, hospital treatment for that specific condition is excluded for 12 months after joining. After 12 months, the condition is covered like any other.
The good news: insurers must prove a condition is pre-existing. You are not automatically excluded just because you have a medical history — and you cannot be rejected, or charged more, for having one.
Understanding exactly what counts as pre-existing tells you what to expect when you claim, and stops the exclusion arriving as a surprise at the worst moment.
Quick reference: the rules
| Aspect | Hospital cover | Extras cover |
|---|---|---|
| Lookback period | 6 months before joining | N/A |
| Exclusion period | 12 months | None — no pre-existing exclusion |
| What is excluded | Treatment for that condition | Nothing |
| After 12 months | Covered like any other condition | Immediate, after the 2-month general wait |
| Burden of proof | The insurer must prove it | N/A |
| Can you dispute it? | Yes — through PHIO | N/A |
The rule in one sentence: if you had signs, symptoms or knowledge of a condition in the 6 months before joining hospital cover, treatment for that condition is excluded for 12 months.
What counts as pre-existing.
Three tests, and meeting any one of them is enough.
The official definition
A pre-existing condition is any condition, ailment, illness or symptom for which you:
It still counts even if you never saw a doctor, were never formally diagnosed, thought it was minor, or ignored the symptoms entirely. A diagnosis is not the trigger — the symptoms are.
The should-have-reasonably-known test
One question decides it: would a reasonable person have sought medical advice?
You should have known
- Persistent chest pain for 3 months
- Ongoing knee pain that stops normal activity
- A lump that is growing
- Blood in urine for weeks
You would not be expected to
- An occasional headache — common, not concerning
- Minor muscle soreness after exercise — normal
- A single episode of indigestion — not persistent
The standard is what a reasonable, prudent person would do in your situation — not what a doctor would have found.
Why six months, and not longer
| The window captures | Why it stops there |
|---|---|
| Recent symptoms, not ancient history | It balances protecting the insurer against being fair to you |
| Conditions being investigated or treated | It stops people joining only once they are sick |
| Symptoms serious enough to warrant attention | It does not penalise a medical history from years ago |
So in practice: symptoms 7 or more months ago are usually not pre-existing — too old. Symptoms 5 months ago could be. Symptoms that are still going on are, without argument.
The 6-month lookback.
The window runs backward from the day you join, and nothing outside it counts unless it is still going on inside it.
How the window is calculated
Join on 1 March 2026, and the lookback period is 1 September 2025 to 1 March 2026.
WHAT MATTERS
Anything inside the window
- Symptoms, diagnosis or treatment between 1 September 2025 and 1 March 2026
- Conditions you knew about during that period
WHAT DOES NOT
Anything before it — with one exception
- Symptoms or conditions before 1 September 2025
- Unless they are ongoing or continuous into the window
Three timelines, three different answers
All three join on 1 March 2026, so all three have the same lookback window. Only the history differs.
EXAMPLE 1 — KNEE PAIN
Pre-existing
- June 2025: twisted the knee, pain started
- September 2025: still in pain
- November 2025: saw a doctor, diagnosed with arthritis
- 1 March 2026: joined hospital cover
Why: the pain was ongoing inside the window, so the start date being before it makes no difference. 12-month exclusion for knee treatment.
EXAMPLE 2 — OLD INJURY, FULLY RECOVERED
Not pre-existing
- January 2025: sprained an ankle
- February 2025: fully recovered, no symptoms
- 1 March 2026: joined hospital cover, 14 months later
Why: recovery came around 7 months before the window even opened, and nothing continued into it. Covered after the 2-month general waiting period.
EXAMPLE 3 — ONGOING CHRONIC CONDITION
Pre-existing
- 2020: diagnosed with diabetes
- 2020 to 2026: ongoing management
- 1 March 2026: joined hospital cover
Why: a known, continuing condition is inside every lookback window, however old the diagnosis. 12-month exclusion for diabetes-related hospital treatment.
Example 2 reads “13 months later” in the source article; January 2025 to 1 March 2026 is 14 months, so the figure is corrected here. The dates themselves, and the conclusion, are the article’s own and are unchanged.
The 12-month exclusion.
It runs from the day you join, it applies to one condition rather than the whole policy, and it ends.
What is and is not excluded
Excluded for 12 months
- Hospital treatment for the pre-existing condition
- Procedures directly related to it
- Complications of it
Not excluded
- Other, unrelated conditions — covered after the 2-month general wait
- The same condition treated in a public hospital, which Medicare covers free
- Treatment once the 12 months are up
One condition, across three years
Joining hospital cover on 1 March 2026 with pre-existing knee arthritis. The exclusion runs to 1 March 2027.
A knee arthroscopy falls inside the exclusion. Public hospital, free, or pay privately at around $8,000.
The exclusion ended on 1 March 2027, so a total knee replacement is covered, less your excess and any doctor gaps.
A revision after the replacement is covered too. The condition is no longer pre-existing at all.
The exclusion is on hospital cover only. Extras has no pre-existing exclusion of any kind — only its standard waiting periods, which are 2 months for general services and 6 to 12 months for major dental.
Check your own dates.
The whole question comes down to two dates and one judgement — whether the condition was live inside the six months before you joined, and whether it was serious enough that a reasonable person would have done something about it.
Work it through
Every rule below is the one this guide publishes: the 6-month lookback, the 12-month exclusion, the 2-month general wait, and the fact that extras has no exclusion at all.
Is it pre-existing? In 10 seconds.
On the rules as published
Pre-existing
6-month lookback12-month exclusion
Hospital cover for this condition
From 1 March 2027
Everything unrelated is covered after the 2-month general wait, from 1 May 2026.
An indication, not a decision — the insurer has to prove a condition is pre-existing, and you can dispute it.
This follows the rules as this guide states them; it is not your insurer’s determination. Two things it deliberately does not do. It does not decide the grey area for you — where the symptoms were minor or one-off it returns arguable, which is the word the article itself uses for those cases, because that is genuinely where the evidence decides. And it takes no view on whether a second, unrelated condition is caught: the exclusion attaches to one condition, so a new and unrelated problem runs on the ordinary 2-month general wait.
How insurers decide.
Not when you join — when you claim. There is no medical exam at application, and you are accepted regardless of your health.
The investigation, step by step
Admission details, the procedure, the diagnosis.
A claims processor reviews it and flags anything that might be pre-existing.
A letter asking for your GP records from the past 6 months. You typically have 30 days to respond.
GP notes, specialist letters and test results, read for evidence of symptoms or a diagnosis inside the lookback.
Pre-existing found: the claim is denied, with the reason explained. Not found: the claim is approved.
What they are looking for
| Evidence | What it looks like |
|---|---|
| Direct | GP notes recording the complaint, a specialist referral naming the onset, a scan taken inside the lookback, a prescription for the condition written during it |
| Circumstantial | Repeat visits for the same complaint, persistent symptoms mentioned in passing, or a diagnosis arriving suspiciously soon after you joined |
The burden of proof is the insurer’s, not yours. You do not have to prove a condition is not pre-existing. If the evidence is ambiguous, the benefit of the doubt goes to you. Records saying you presented with knee pain 7 months before joining are outside the window and cannot support an exclusion; records saying you mentioned it 5 months before can.
Records and evidence.
The decision is usually made on a few lines in a GP file, so it is worth knowing what those lines say.
What a GP note contains
Clinical notes typically record the date of consultation, the presenting complaint, the symptoms described, examination findings, the diagnosis or working diagnosis, treatment prescribed, and the follow-up plan.
A REAL-SHAPED GP NOTE
15 October 2025
- Presenting complaint: right knee pain, 6-week duration
- History: gradual onset knee pain, worse with stairs
- Examination: tenderness medial joint line, reduced range of motion
- Assessment: likely osteoarthritis
- Plan: trial NSAIDs, physio referral, review in 6 weeks
Join on 1 November 2025 and this note sits squarely inside the lookback. Clear evidence of knee symptoms: the knee is pre-existing.
What insurers ask for, and what they can see
| Source | Why it matters |
|---|---|
| GP records | The most important and the most comprehensive |
| Specialist letters | Referrals and consultation notes |
| Test results | X-rays, MRIs, blood tests, scans |
| Hospital records | Previous admissions and emergency visits |
| Prescription records | Medication prescribed for the condition |
| Access | Only with your written consent — though refusing to provide records may itself result in the claim being denied |
Read your own file first
Ask your GP for your records from the past 6 months. They usually arrive within 7 to 14 days, sometimes for a small fee of around $20 to $50, as printed notes or a digital file. Reading them tells you what the insurer will read.
WHEN A NOTE IS WRONG
Notes can carry errors
- Incorrect dates
- The wrong symptoms recorded
- Complaints attributed to the wrong visit
- Example: the note reads knee pain for 9 months when you said occasional discomfort, recently
WHAT TO DO
Correct it through the GP
- Request a correction from the practice
- Get the amended record
- Provide it to the insurer with an explanation
Correct genuine errors. Never alter or falsify a record. That is fraud, and it costs far more than the claim.
Disclosure and honesty.
Being pre-existing and failing to disclose are two different things, and only one of them can cost you the whole policy.
The difference that matters
| Pre-existing condition | Non-disclosure | |
|---|---|---|
| What happened | The condition existed in the 6 months before joining | You deliberately lied on the application, or hid a condition you were asked about |
| Consequence | A 12-month exclusion on that one condition | The insurer can void the entire policy |
| Your membership | Unaffected — you are still accepted | Can be cancelled |
The same condition, two ways of handling it
The application asks whether you have any medical conditions. You have had diabetes for two years.
HONEST
You say yes, diagnosed two years ago
- Accepted
- Diabetes is pre-existing — 12-month exclusion on diabetes treatment
- Everything else covered normally
DISHONEST
You say no
- Three months later you need a diabetes-related admission
- The insurer finds the condition predated the policy and that you lied
- Claim denied and the whole policy voided for non-disclosure
Non-disclosure costs you cover for everything. Being pre-existing costs you one condition for twelve months. That is the entire trade.
What if you genuinely did not know?
You are not required to disclose what you do not know about. A cancer growing with no symptoms and no diagnosis, discovered three months after joining, is not pre-existing — because you had no symptoms, no knowledge, and no reason to have sought advice.
If all three answers are no, it is not pre-existing — even if the condition technically existed.
Disputing a decision.
A pre-existing denial is not final. The insurer carries the burden of proof, and there is a free, independent umpire above them.
When it is worth disputing
- You believe the condition was not pre-existing
- The insurer’s evidence is weak
- Your medical records do not support what they are claiming
- The timeline sits outside the 6-month lookback
- The symptoms were minor and would not have warranted attention
Step 1 — internal review
Usually 2 to 4 weeks.
Say plainly that you want to dispute the pre-existing condition denial, and ask for a different assessor.
A GP letter setting out the timeline is the strongest single thing you can send.
They may request more information, then either uphold the denial or approve the claim.
Step 2 — the Private Health Insurance Ombudsman
Free, independent dispute resolution. Typically 4 to 12 weeks. Phone 1800 640 695, or privatehealth.gov.au/ombudsman.
| Stage | What happens |
|---|---|
| You complain | Online or by phone |
| PHIO gathers evidence | It requests information from you and from the insurer |
| PHIO reviews | All the evidence, from both sides |
| PHIO decides | A recommendation or a finding — it can order the insurer to pay, determine the condition is not pre-existing, or uphold the denial where the evidence supports it |
| The insurer complies | It must follow the PHIO decision |
Evidence that actually helps
| Evidence | What it establishes | Weight |
|---|---|---|
| GP letter | Confirms when you first presented with the condition, and whether that was inside or outside the lookback | Strongest |
| Your own timeline | Joined 1 March, symptoms began 15 March — specific dates, not impressions | Strong |
| Test results after joining | Tests showing a new condition, with nothing earlier indicating it existed | Strong |
| Witness statements | A family member confirming there were no symptoms before you joined | Supporting only |
Two disputes that succeed
DISPUTE 1 — A MISRECORDED DURATION
The note says months, you said weeks
- The GP recorded a duration far longer than the one you described
- The pain had actually run about three weeks, from 1 February 2026, a month before joining
- Inside the lookback, but very recent, minor, and the visit was precautionary
The argument: the record overstates the duration, and the symptoms would not have prompted a reasonable person to act.
DISPUTE 2 — SUSPICIOUS TIMING ONLY
Gallstones found two months after joining
- No symptoms at all before joining
- The first symptoms appeared afterward
- A GP letter confirms there were no gallbladder symptoms prior to the policy
The argument: timing alone is not evidence. The condition developed after joining, so it is not pre-existing.
The source article works through a first version of Dispute 1, then corrects itself mid-page and supplies the version above. Only the corrected one is carried here.
Extras has no pre-existing exclusion.
None. You can join extras with a condition you have had for years and claim on it as soon as the ordinary waiting period is served.
Three conditions you already have
| What you already have | Waiting period | Then |
|---|---|---|
| Chronic back pain for two years | 2 months — general extras | Claim physiotherapy for that same back pain |
| Cavities needing fillings | 2 months — general dental | Claim the dental work |
| A child with crooked teeth | 12 months — orthodontics | Claim toward braces |
In every case there is no exclusion for the pre-existing condition itself — only the standard waiting period for the service.
Why hospital and extras differ
Hospital
- High-cost claims — surgeries in the $10,000 to $50,000 range
- A real risk of people joining only when they need surgery
- The exclusion is what stops the system being gamed
Extras
- Lower-cost claims — typically $200 to $2,000
- Annual limits already cap the insurer’s exposure
- Waiting periods alone are protection enough
Strategy, and what people get wrong.
If you already have a condition, there are only two sensible plays — and most of the folklore about pre-existing conditions is false.
Two ways to time it
OPTION 1
Join now and serve the 12 months
- You cannot claim for that condition for 12 months
- Everything else is covered after the 2-month general wait
- The condition is covered from month 13 onward
OPTION 2
Treat it publicly first, then join
- Use a public hospital for the current condition, free
- Join once treatment is complete and the condition is no longer active
- With no symptoms inside the new lookback, it is likely not pre-existing
Worked through: public knee surgery in March 2026, recovery April to June, joining in January 2027. The lookback runs July 2026 to January 2027, the knee has been symptom-free throughout, and it is not pre-existing.
If the condition is chronic
A condition like diabetes or arthritis will be pre-existing whenever you join — that is simply the arithmetic of an ongoing condition against a 6-month lookback. Join anyway.
Use the public system for that condition during the first 12 months if you need to. You are covered for everything else from the end of the 2-month general wait, and covered for the condition itself from month 13. The 12 months pass either way; the only question is whether you are insured at the end of them.
Six things people believe that are not true
| The belief | Verdict | What is actually true |
|---|---|---|
| I will be rejected if I have a pre-existing condition | False | Community rating means insurers must accept every applicant regardless of health. The condition only affects what is covered in the first 12 months |
| Pre-existing means I am never covered for it | False | It is a 12-month exclusion, not a permanent one. After that the condition is covered like any other |
| If I do not tell them, they will not know | Dangerous | They find out when you claim, because medical records show the history — and non-disclosure voids the whole policy, not just that claim |
| I can switch insurers to reset the exclusion | False | Pre-existing status transfers with you. With continuous cover the clock keeps running from the original join date, so switching neither resets nor restarts it |
| Pre-existing applies to extras too | False | Extras has no pre-existing exclusion at all — only the standard waiting periods |
| Old conditions are always pre-existing | False | Only what falls inside the 6-month lookback counts. An appendectomy five years ago is not pre-existing — there is no appendix and nothing unresolved |
Frequently asked questions.
No. Insurers must accept everyone regardless of health status — they cannot reject an applicant, and cannot charge more for a pre-existing condition. That is what community rating means: everyone of the same age on the same policy pays the same rate.
A pre-existing condition affects only what is covered in the first 12 months. It has no bearing on whether you are accepted.
It depends on whether you should have known. Something minor and long resolved is reasonable to forget, and forgetting it is not non-disclosure.
Recent surgery, ongoing treatment or a diagnosed illness is not reasonable to forget, and could be treated as non-disclosure. Take your time over the application and go through your medical history properly.
Yes. Medicare and the public system are always available, and free. During the exclusion your private cover will not pay for the pre-existing condition, but it does cover everything else — so many people use the public system for that one condition and their policy for the rest.
Once the 12 months are up, you can choose private or public for it like any other condition.
Get a letter from them and dispute the decision. The letter should state when the symptoms first appeared, the timeline of how the condition developed, and their opinion on whether it existed inside the 6-month lookback.
Submit it to the insurer for internal review, and to PHIO if the insurer upholds the denial. PHIO weighs medical opinion heavily in these disputes.
The dispute process
No. Pre-existing status is assessed per person, not per policy. If you have a pre-existing knee condition, the 12-month exclusion is yours alone — your partner and children are covered after the ordinary 2-month general wait.
No — adding hospital cover is the same as joining hospital cover from scratch. Three years of extras does nothing for it.
The hospital waiting periods start from zero (2 months and 12 months), and the pre-existing exclusion applies with the 6-month lookback measured from the date you add the hospital component. Hospital and extras are completely separate.
How waiting periods work
The exclusion continues on its original timeline. Join Bronze on 1 March 2026 with a pre-existing knee, upgrade to Silver on 1 September 2026, and the exclusion still ends on 1 March 2027 — twelve months from the original join date. Upgrading does not reset the clock.
Services that exist only in Silver carry their own new waiting period, but the pre-existing timeline runs from when you first joined.
No. Community rating means the same tier at the same age costs the same, whatever your health.
The only things that change your premium are your age, the policy tier, the excess you choose, and any Lifetime Health Cover loading.
Lifetime Health Cover loading
It becomes pre-existing if the symptoms or diagnosis fall inside the 6-month lookback. Diagnosed with diabetes in January 2026 with no cover, joining hospital cover in June 2026: the lookback runs December 2025 to June 2026, the diagnosis sits inside it, and the 12-month exclusion applies.
You cannot develop a condition while uninsured, join, and expect it covered straight away.
You do not have to — the burden of proof sits with the insurer. But you can help: a GP letter confirming there were no symptoms before you joined, a specific date on which the symptoms began, test results from after joining showing a new condition, and the absence of any earlier history of it.
If the evidence is unclear, the benefit of the doubt goes to you. If the insurer's evidence is weak, dispute it through PHIO.
Check your own dates
Next steps.
A pre-existing condition costs you twelve months on one thing. Not disclosing it costs you everything — and joining later costs you the twelve months all over again.
If a claim is denied as pre-existing
- Ask the insurer for the evidence the decision was based on
- Get your own GP records and check the dates against the 6-month lookback
- Request an internal review, with a GP letter setting out the timeline
- Contact the Private Health Insurance Ombudsman on 1800 640 695 if the review fails — it is free and independent
General information only: this guide provides general information about pre-existing conditions in health insurance. Specific determinations depend on individual circumstances and medical evidence. This is not legal or medical advice.
Not insurance or medical advice: for specific questions about whether your condition is pre-existing, contact your insurer. For medical questions, consult a healthcare professional.
Dispute rights: if your claim is denied for pre-existing reasons, you have the right to dispute it through your insurer and through the Private Health Insurance Ombudsman.
Data currency: pre-existing condition rules are stable. Information current as of February 2026.
Sources: information reflects standard industry practices and government regulations as of February 2026.
Independence: we are an independent comparison service. We may receive commissions from insurers when users purchase policies. This does not affect how we present pre-existing condition information.
Last updated: February 26, 2026 · Next review scheduled: May 2026 · Found pre-existing condition information incorrect?Contact us
