The basic rule
UK private health insurance is designed to cover new, acute conditions — illnesses and injuries that start after your policy begins and that are likely to respond to treatment. Conditions you already have (or have had recently) are normally excluded, at least at first.
That doesn't make cover pointless if you have a medical history. Everything else is still covered — and for many people, the biggest value of the policy is fast access to diagnosis and treatment for things that haven't happened yet, such as cancer or a joint problem.
The two main types of underwriting
Moratorium underwriting is the most common for individual policies. You don't fill in a medical questionnaire. Instead, the insurer automatically excludes any condition you've had symptoms, treatment or advice for in the last five years (some insurers use three). If you then go two continuous years on the policy without any trouble from that condition, it can become covered.
Full medical underwriting (FMU) means you declare your medical history up front. The insurer then tells you in writing exactly what's excluded. It takes a little longer, but there are no surprises at claim time — and conditions from many years ago that are fully resolved may be accepted without exclusion.
| Moratorium | Full medical underwriting | |
|---|---|---|
| Medical questionnaire | No | Yes |
| When you learn what's excluded | When you claim | Before you buy |
| Can old conditions become covered? | Yes, after a clear period (usually 2 years) | Usually only if the insurer reviews an exclusion |
| Best for | Little or no recent history | A clear picture of cover, or older resolved conditions |
Chronic conditions
Long-term conditions that need ongoing management rather than a cure — such as diabetes, asthma, high blood pressure, COPD or some arthritis — are generally not covered for routine care by any UK insurer, even if they start after you join. The NHS continues to manage these. What private cover can help with is the diagnosis of a new condition, and acute flare-ups or related episodes, depending on the policy.
Insurers that help with existing conditions
A small number of insurers offer options that go further than the market standard:
- General & Medical offers an option to cover up to two pre-existing conditions, within annual limits.
- Saga has an option that can cover controlled high blood pressure.
- Vitality is willing to waive some pre-existing mental health exclusions.
- AXA Health and Saga use a three-year look-back for moratorium rather than five, which can help if your history is a few years old.
Options and terms change, so a specialist should confirm what's available for your specific condition before you buy.
Switching without losing cover
If you already have a policy and have claimed for something, moving to a new insurer on a fresh moratorium could mean that condition becomes excluded. Ask about switch terms (also called continued personal medical exclusions, or CPME), which carry your existing underwriting over so you don't lose cover you've built up.
Covered through work?
Company schemes — especially larger ones — can offer medical history disregarded (MHD) underwriting, which covers pre-existing conditions from day one. If your employer offers health insurance, it's often the best route to cover for existing conditions. See our business health insurance guide.
Questions and answers
Can I get health insurance if I have a pre-existing condition?
Yes. Having a pre-existing condition doesn't stop you buying a policy — it usually means that particular condition (and anything related to it) is excluded, while everything new that develops after you join is covered in the normal way.
What counts as a pre-existing condition?
Broadly, any illness, injury or symptom you've had, or received treatment, medication or advice for, before your policy starts. Under moratorium underwriting insurers typically look back five years (some, such as AXA Health and Saga, use three); under full medical underwriting you declare your history on an application form.
Will a pre-existing condition ever become covered?
Under moratorium underwriting it can. If you go a continuous period — usually two years after joining — without symptoms, treatment, medication or advice for that condition, it can become eligible for cover. Under full medical underwriting, an exclusion usually stays in place unless the insurer agrees to review it.
Is moratorium or full medical underwriting better?
Neither is better for everyone. Moratorium is quicker to set up and can bring old conditions back into cover over time, but you only find out what's excluded when you claim. Full medical underwriting takes longer and may exclude conditions permanently, but you know exactly where you stand from day one. If you have a complex or recent history, full underwriting often gives more certainty.
Are chronic conditions like diabetes or asthma covered?
The ongoing management of chronic conditions — such as diabetes, asthma, high blood pressure or arthritis — is generally not covered by UK private health insurance, whether or not you had them before joining. Policies are designed for acute conditions that respond to treatment. However, a flare-up or a new acute problem may be covered, depending on the policy wording.
Do I have to declare conditions I've had in the past?
Under full medical underwriting, yes — you must answer the insurer's questions honestly and completely. Missing something out can lead to a claim being refused or the policy being cancelled. Under moratorium underwriting you usually don't complete a medical questionnaire, but your history is checked when you claim.
If I switch insurer, will I lose cover for conditions I've claimed for?
Not necessarily. Many insurers offer 'switch' or continued personal medical exclusions (CPME) terms, which carry your existing underwriting over to the new policy rather than starting from scratch. A specialist can check whether switching terms are available before you move.
Insurers worth comparing
Further reading
- Pre-Existing Conditions and Health Insurance: What's Covered, What Isn't
- Moratorium vs Full Medical Underwriting: How Health Insurance Actually Works
- Mental Health Cover in Private Health Insurance: What's Included in 2026