Term Life Insurance: Sizing and Timing the Coverage That Actually Matters
The question a term policy answers is narrow and specific: if you die during this fixed window, does the person or people depending on your income get a lump sum large enough to replace it. That narrowness is exactly why term insurance is cheap, and why it remains the right default for nearly every working adult with dependents, despite an insurance industry that earns far more commission steering people toward something more complicated.
The core principle
Term life insurance pays a fixed death benefit if the insured dies within a specified term, commonly 10, 20, or 30 years, and pays nothing if the insured outlives the term. It builds no cash value and has no investment component; the premium buys pure mortality risk transfer and nothing else. That simplicity is the source of its low cost relative to permanent insurance, which bundles a death benefit together with a savings or investment feature and charges accordingly for both.
The correct way to think about term insurance is as a replacement for a specific, identifiable, and temporary risk: the risk that your dependents lose your future income before they no longer need it. A young parent's need for coverage is large and long, because a working lifetime of income replacement for young children is worth a great deal and the need will not disappear for two decades or more. A near-retiree with grown children, a paid-off mortgage, and a substantial investment portfolio may have almost no ongoing need at all, because their human capital, the present value of future income that insurance is meant to replace, has been mostly converted into financial capital that can already support survivors on its own. Term insurance is priced to match this reality: coverage is cheap while the insured is young and healthy, and both the need for it and, if renewed, its cost, tend to shrink and rise respectively as time passes.
Underwriting determines the premium primarily through age, health, tobacco use, and the length and size of the policy. A healthy nonsmoker in their thirties pays a small fraction of what the same face amount costs a smoker in their fifties, which is one more reason to lock in a level-premium term policy early, while the health and age discount is largest, rather than waiting and buying coverage piecemeal later at a steadily worse price.
How the math works
Example 1: term versus permanent, the same coverage amount. A healthy 35-year-old nonsmoker can typically buy $2,000,000 of 20-year level term for roughly $1,400 a year, a rate that stays fixed for the full 20 years. Over the full term, total premium paid works out to $1,400 x 20 = $28,000. A permanent whole life policy with the same $2,000,000 face amount for the same person commonly runs in the range of $18,000 to $24,000 per year, because a large share of the premium is funding the policy's cash value and lifetime guarantee rather than pure mortality risk. Using a representative figure of $19,000 a year, the same 20-year stretch costs $19,000 x 20 = $380,000, more than thirteen times the term premium for an identical death benefit over that period. The classic "buy term and invest the difference" approach takes that $17,600 annual gap and invests it instead, which historically outgrows the whole life policy's cash value by a wide margin over two decades, though the comparison depends on realized investment returns and the discipline to actually invest the difference rather than spend it.
Example 2: laddering coverage to match a shrinking need instead of overpaying for one flat policy. A family determines they need $1,500,000 of coverage while both children are young and a mortgage is outstanding, an amount they estimate will decline to a permanent $500,000 need for spousal income replacement once the mortgage is paid off and the children are financially independent in about ten years. Buying a single 30-year, $1,500,000 term policy prices the full $1,500,000 of coverage for all 30 years, even during the last two decades when the family only needs $500,000. Laddering splits the coverage instead: a 10-year, $1,000,000 term policy layered on top of a 30-year, $500,000 term policy. If a 20-year, $1,500,000 policy for this family runs about $2,700 a year, the laddered combination, roughly $2,100 for the 10-year $1,000,000 layer plus $650 for the 30-year $500,000 layer, costs about $2,750 for the first ten years, similar to the single policy, but only $650 a year for the remaining twenty years instead of $2,700, saving roughly $2,050 a year, or about $41,000 total, over the last two decades of coverage the family no longer fully needs.
How it shows up in real portfolios
A new parent in their late twenties or early thirties with a mortgage and young children is the textbook case: young enough for very cheap rates, but with a large and immediate income-replacement need if something happened to them, since their financial capital is still small relative to the future earnings a family depends on. Sizing coverage at roughly ten to fifteen times annual income, adjusted for outstanding debt and the number of working years remaining, is a reasonable starting rule of thumb, refined by an actual calculation of the family's specific expenses, debts, and savings goals.
A high-earning professional early in a career, such as a physician still years from finishing training, is an unusually strong case for term insurance precisely because their human capital, the present value of decades of future high income, is enormous relative to their current invested assets, which may be near zero or even negative because of student debt. A resident physician with $300,000 in expected lifetime earnings still ahead of them, a spouse, and young children carries a much larger insurable need than their current bank balance would suggest, and term insurance is the only cost-efficient way to protect that gap.
A self-employed spouse whose unpaid household labor, primarily childcare, would otherwise cost tens of thousands of dollars a year to replace with paid care is a frequently underinsured case: because that spouse draws no salary, families sometimes skip insuring them entirely, missing that the financial impact of losing that labor is very real and calculable.
Actionable breakdown
- How to size coverage:
- Estimate years of income replacement needed.
- Add outstanding debt: mortgage, loans, tuition plans.
- Subtract existing liquid assets and other coverage.
- How to choose the term length:
- Match it to when the largest need ends.
- Consider laddering two or three policies.
- Lock in level premiums while young and healthy.
- Before applying:
- Compare quotes across several insurers.
- Confirm the policy is level-premium and convertible.
- Check the insurer's financial strength rating.
Common pitfalls
- Letting a term policy lapse just before retirement because the term expired, only to discover a real ongoing need still exists and new coverage at an older age is far more expensive or unavailable due to health changes.
- Relying solely on employer group coverage, which is typically capped at one or two times salary and is not portable if you change jobs or are laid off.
- Being sold a permanent policy through an emotional pitch about "wasting money on rent-like term premiums," when the actual math of buying term and investing the difference wins for the large majority of buyers who need protection, not a savings vehicle.
- Underinsuring a stay-at-home or lower-earning spouse because their labor does not appear on a pay stub, ignoring the very real replacement cost of the work they do.
Related concepts
For the full mechanics and alternatives, see the primary entry on life insurance, term and the contrasting entry on life insurance, whole and universal. Coverage needs are ultimately a function of human capital, and the closest sibling risk worth insuring alongside it is covered under disability insurance. For a full framework, see the guide on disability and life insurance.
The bottom line
Buy enough term insurance to fully replace your income for as long as someone depends on it, and let the policy expire once that dependency does.