A term policy covers a fixed window and most of them never pay out, because most people outlive the term. A whole of life policy has no end date: provided the premiums are maintained, it pays out whenever you die.

That certainty is why it costs considerably more than term cover for the same sum assured. You are not buying protection against dying early; you are pre-funding a payment that will definitely happen.

The clearest use is funding a known inheritance tax liability. If an estate is expected to face a substantial IHT bill, the tax is payable before much of the estate can be released, which can force the sale of a property or a business at speed and at a poor price.

A whole of life policy written in trust puts a lump sum in the beneficiaries' hands, outside the estate and outside the IHT calculation, at exactly the moment the bill falls due. For couples this is usually arranged as a second-death joint policy, because that is when the liability normally crystallises.

Funeral costs and leaving a defined legacy are the other common reasons, though for smaller sums an over 50s plan may be the more proportionate route.

Guaranteed premiums are fixed for life at outset. They cost more at the start, and they cannot rise. What you agree at 55 is what you pay at 85.

Reviewable premiums start lower, then are reviewed periodically, typically after ten years and at intervals after that. At each review the premium can increase, sometimes very substantially, because it is being re-set against your age at that point. Policyholders who took reviewable cover cheaply in their fifties have faced increases in later life large enough to force them to reduce the sum assured or give the policy up altogether, having paid in for decades.

Neither is automatically wrong, but this is the single most consequential choice in a whole of life policy and it deserves more than a footnote. We will show both, with the review mechanics spelled out.

Whole of life cover only pays out for as long as premiums are maintained. Stop paying and the cover normally ends. Some policies carry a surrender value, which may be a small fraction of what has been paid in and is not a savings product in any meaningful sense; many carry none at all. Whether a policy has one, and what it is worth, varies entirely by insurer and by contract.

Because these policies are meant to run for the rest of your life, affordability at 80 matters as much as affordability today. That is the calculation worth doing before you start, not after.