underwriting and risk classification
If an insurer charged a 25-year-old marathon runner and a 60-year-old heavy smoker the same premium, the healthy applicant would feel overcharged and walk away, leaving the insurer with mostly high-risk customers — a death spiral. To price fairly and stay solvent, insurers must sort applicants by how risky they are. That sorting is risk classification, and the process of investigating each applicant is underwriting.
Underwriting gathers information — age, sex (where allowed), medical history, build, blood pressure, smoking, family history, occupation, hobbies — to estimate an applicant's mortality risk, then assigns them to a risk class. Typical classes run from preferred (or preferred plus), for the healthiest with the lowest premiums, to standard, the average baseline, down to substandard (or rated) for higher-risk applicants who pay a surcharge often expressed as a percentage of the standard rate — a 'table 4' rating might mean 200 percent of standard. Some applicants are declined entirely, or offered exclusions for a specific hazard. For example, two 45-year-olds might both get cover, but the non-smoking preferred risk pays half what the smoking substandard risk pays.
Actuaries build separate or adjusted mortality assumptions for each class and rely on this sorting to keep the pricing self-consistent. The deep purpose is to fight adverse selection — the tendency for those who know they are high-risk to buy the most insurance. The honest caveats: classification must be based on genuine risk and is bounded by anti-discrimination law (for instance many jurisdictions restrict or ban the use of sex or genetic test results), and a class is a statistical average, not a verdict on any one person's actual lifespan.
Two non-smoking 45-year-olds apply for 500,000 of term cover. One is athletic with great labs and family history and qualifies as preferred plus; the other is overweight with high blood pressure and a heart condition in the family, and is rated substandard at 175 percent of standard. Both get cover, but the preferred-plus premium might be 600 a year versus around 1,500 for the rated case.
Underwriting sorts applicants into classes — preferred, standard, substandard — to price each fairly.
A risk class is a statistical grouping, not a prediction of when you personally will die; plenty of substandard lives outlive preferred ones. Classification must reflect real risk and obey anti-discrimination rules — it is not licence to use any variable an insurer likes.