A policyholder with one substantial claim sometimes renews more cheaply than one with several small ones. Frequency and severity carry different predictive weight.
Frequency signals something about the risk
Claims arise from a combination of circumstance and behaviour. A pattern of repeated small claims suggests something persistent about the exposure rather than bad luck.
Insurers price forward, so what matters is what a claim history predicts about future cost. Repetition predicts repetition.
A single large loss, particularly from a one-off event, carries much weaker information about what next year will look like.
Fixed handling costs dominate small claims
Every claim incurs administration regardless of size, including assessment, correspondence and settlement. On a small claim these costs can approach the payout itself.
Several small claims therefore consume disproportionate expense relative to the amount transferred, which is inefficient for the insurer and reflected in pricing.
Deductibles exist partly to remove this category, since a claim below the excess never enters the process at all.
Raising the excess removes more of the small-claim volume than the payout figures alone suggest, because it removes the handling cost attached to each one as well as the payment.
Large losses are spread differently
Severe claims are often shared with reinsurers under arrangements agreed in advance. The direct insurer's own exposure to any single large loss is capped.
Because that cost is already distributed, one large claim affects the insurer's own result less than the gross figure suggests.
Small claims sit entirely with the primary insurer, so their cost is borne in full within the pool being priced.
No-claims arrangements amplify the effect
Discount structures typically step back by a fixed amount for each claim rather than in proportion to its size. Two small claims can cost more discount than one large one.
Because the discount is applied to the whole premium, losing steps has an effect that persists across several renewals rather than one.
This is why the decision to claim on a minor loss is an arithmetic question involving the excess, the payout and the discount at stake.
What this implies about cover
Insurance is most valuable against losses that would be difficult to absorb, and least efficient against ones that would merely be inconvenient.
Choosing a higher excess deliberately removes the small-claim category, usually reducing premium and preserving the discount structure.
The appropriate level depends on what a household could comfortably meet from reserves, which is a personal judgement rather than a general rule.