Income protection and critical illness cover both exist to soften the financial impact of ill health, and people often assume one makes the other unnecessary. In practice they solve different problems, and understanding the difference matters more than the names suggest.
What income protection actually does
Income protection pays a regular, ongoing income — typically a proportion of your normal earnings — if you're unable to work due to illness or injury, for as long as you remain unable to work, up to the policy's chosen end date (often your planned retirement age). It's triggered by your inability to do your job, not by a specific diagnosis. That means it can pay out for conditions that critical illness policies never touch, such as long-term back problems, stress-related illness, or a slow recovery from surgery.
Most policies have a "deferred period" — a wait, often matching how long your employer continues paying sick pay, such as 4, 13 or 26 weeks — before payments begin.
What critical illness cover actually does
Critical illness cover pays a single, tax-free lump sum on diagnosis of one of a defined list of serious illnesses — commonly certain cancers, heart attacks, strokes and a number of other named conditions — provided the diagnosis meets the policy's specific definition. It doesn't matter whether you continue working or not; the trigger is the diagnosis itself, not your ability to earn.
Side by side
| Income protection | Critical illness cover | |
|---|---|---|
| Payout type | Regular income, ongoing | One-off lump sum |
| Trigger | Inability to work | Diagnosis of a listed condition |
| Typical use | Replacing lost salary long-term | Clearing debt, funding treatment or adapting your life |
| Covers stress, back pain, etc. | Often yes | Rarely |
| Pays if you recover and return to work quickly | Stops once you're fit to work | Pays regardless, once diagnosed |
Why some people hold both
The two policies are complementary rather than duplicative. Critical illness cover can clear a mortgage or fund immediate costs the moment something serious is diagnosed, while income protection keeps replacing lost salary for as long as you're actually off work — including for illnesses that critical illness policies simply don't cover. A household with a large mortgage and no savings buffer is often more exposed to a long absence from work than to a single serious diagnosis, which is why some advisers suggest prioritising income protection first, then adding critical illness cover if budget allows.
Common misconceptions
- That critical illness cover is a substitute for income protection — it only pays once, for a limited list of conditions, and not at all for the majority of reasons people actually take long-term sick leave.
- That income protection pays your full salary — most policies replace a percentage, often around 50–70%, partly to preserve the incentive to return to work when able.
- That both policies will pay out for the same event — they can, since a serious diagnosis might trigger a critical illness lump sum and, if it also stops you working, an income protection claim as well.
What to do next
Check what your employer already provides — some offer enhanced sick pay or even group income protection — before buying your own policy, since that changes how much extra cover you need. Then decide whether your bigger risk is a long absence from work or the upfront cost of a serious diagnosis, and prioritise accordingly.