How does BMI affect the cost of life insurance?

BMI can be one part of a life-insurance application, but it does not determine the outcome on its own. Each insurer uses its own underwriting criteria and assesses the policy being applied for. This guide explains what BMI measures, how it may be considered for life insurance, and how to approach a quote accurately.

What is BMI?

BMI (body mass index) is calculated by dividing weight in kilograms by height in metres squared. For adults, it is commonly used as a screening measure. General adult categories include:

• BMI below 18.5 - underweight

• BMI between 18.5 and 24.9 - healthy weight range

• BMI between 25 and 29.9 - overweight

• BMI between 30 and 34.9 - obesity class 1

• BMI between 35 and 39.9 - obesity class 2

• BMI of 40 or more - obesity class 3

These are clinical screening categories, not insurer pricing bands or diagnoses. BMI cannot distinguish muscle from fat, and clinical interpretation can differ for some ethnic backgrounds and for older adults. NICE guidance sets out these interpretation considerations.

How can BMI affect life insurance?

For individually underwritten life insurance, BMI may be considered alongside the amount and term of cover, age, smoking status, medical history and other information in the application. Depending on the insurer and product, the outcome may be standard terms, an increased premium, a request for further information, or no offer for that particular cover.

BMI alone cannot tell you which outcome will apply. Published insurer guidance shows that BMI treatment can vary by product and age, and that other underwriting factors can affect the decision. A premium loading, where applied, is an addition to the relevant standard premium; it is not a universal cash price or a guarantee of what another insurer will charge.

Critical illness cover has its own assessment and policy conditions, so it should not be treated as interchangeable with life insurance. Private medical insurance can also have product-specific terms; those terms do not establish a general rule for life cover.

Why might an insurer ask about BMI?

Insurers use health information to assess the risk they are being asked to cover. At a population level, higher adiposity is associated with health conditions including type 2 diabetes, cardiovascular conditions, osteoarthritis and some cancers. That does not predict an individual’s health, life expectancy or premium. BMI is only one part of the information an insurer may consider.

What about underweight?

A low BMI may prompt further assessment in some cases. For example, the NHS notes an association between being underweight and fracture risk in older adults, but this does not establish a particular insurance price.

What about age?

Age at application can affect a life-insurance premium, as can the insurer’s product-specific approach to BMI. It is not reliable to compare percentage loadings between people of different ages and assume that this shows the difference in their total premium. The underlying premium and the rest of each application may differ.

How to prepare for a life-insurance quote

Use accurate, current height and weight when answering an insurer’s questions. You may also be asked about smoking, medical history, medication, the cover amount and the policy term. In some cases, an insurer may ask for further evidence before it can assess an application. Accurate information matters: material inaccuracies can affect a claim. That does not mean every mistake has the same consequence, but it is a good reason to check your answers carefully. If your circumstances are more complex, an adviser can help you understand the questions and compare the available options without promising a particular outcome.

Does BMI always change the cost of life insurance?

No. BMI may be relevant to an insurer’s assessment, but there is no insurer-wide cutoff or guaranteed premium change. The terms available depend on the insurer, the product and the full details of the application.

Can I still get life insurance if my BMI is high or low?

Possibly. A high or low BMI does not, on its own, determine whether cover will be offered. An insurer may offer standard terms, apply an increased premium, ask for more information or decide not to offer that particular policy. A personal quote is the appropriate way to find out.

If you have concerns about your health, speak to a qualified clinician. For policy terms, use the insurer’s questions and a personal quote rather than relying on general BMI bands.