Start with the job the policy does
A term life policy has one job: if you die during your working years, it replaces the financial support your family would lose. That means the right size isn't a mystical number — it's the sum of what your people would need. Income to live on, debts to retire, a mortgage to keep, tuition down the road.
It also means life insurance isn't just for the primary earner. A stay-at-home parent's work — childcare, transportation, household management — would cost real money to replace, and a policy on that parent is often the most overlooked piece of a family's plan.
The quick method: a multiple of income
The fastest rule of thumb is to carry roughly ten to twelve times your annual income. It's blunt, but it gets most families into a sensible range in ten seconds, and it errs toward enough rather than too little. If you want one number to sanity-check any agent's recommendation, this is it.
The multiple works because a lump sum that size, prudently invested, can generate income support for many years while the family adjusts. Families with young children or a single income often size toward the top of the range — or above it.
The tailored method: DIME
DIME stands for Debt, Income, Mortgage, and Education — add the four together for a personalized target. Debt: everything outside the mortgage, plus final expenses. Income: your annual income times the number of years your family would need it (many people use the years until their youngest is independent). Mortgage: the payoff balance. Education: an estimate for each child's schooling.
Then subtract what you already have: existing savings earmarked for these goals and any coverage through work. A note of caution on that last one — employer group coverage usually ends when the job does, so most planners treat it as a bonus rather than the foundation.
Picking the term length — and keeping it affordable
Match the term to your longest obligation. If your youngest is two and your mortgage has 28 years left, a 30-year term covers the whole arc; if the kids are nearly launched and the house is nearly paid, 10 or 15 years may do. Some families ladder policies — say, a larger 20-year policy plus a smaller 30-year one — so coverage steps down as obligations shrink.
Term insurance is generally most affordable when you're young and healthy, and level-premium policies lock the price for the full term. Since carriers underwrite health very differently, the same person can get noticeably different quotes for identical coverage — which makes comparison shopping the easiest money you'll save on the whole exercise.