How it works
A comprehensive-versus-liability crossover solves the oldest question in auto coverage: at what car value does physical-damage insurance stop being protection and become expensive sentiment? Three lenses converge. The deductible-ceiling rule notes that collision and comprehensive can never pay more than value minus deductible, so once that ceiling sinks beneath roughly ten deductibles the coverage's best case barely clears its worst-year cost. The premium-density rule divides the two lines' combined premium by market value — past ten percent annually, the policy is consuming the asset itself. And the expected-recovery lens multiplies claim frequency by realistic severity, exposing the raw deal plainly: insurers load premiums above expected payouts by design, so pure expectation always favors dropping first, which is precisely why liquidity rules rather than expected values must arbitrate. This calculator computes all three and binds the crossover to the stricter signal, then translates the stakes into plain time — how many premium-years equal one replaced car. On typical aging-beater numbers the verdict arrives decisively: $840 a year defending a $5,300 asset behind a $4,800 ceiling, expected recovery of barely $130, and five-plus premium-years per replacement. The counterweight stays human: dropping coverage converts certain premium into uncertain exposure, sustainable only when a totaled car is a nuisance rather than a crisis.
Formula
ceiling = max(0, value - deductible) | crossover = min(10 x deductible, premium / 10%) | expected recovery = odds x (value x severity % - deductible)
Tips
- Pull collision and comprehensive separately off your declarations page — liability never counts in this test.
- Raise the deductible before dropping coverage; the middle step often restores sanity without full exposure.
- Self-fund the dropped premium into a repair account so a write-off annoys rather than wrecks you.
- Re-run after every market-value slide — depreciation, not decisions, moves this crossover fastest.
- Lenders forbid the drop entirely while a lien exists; this math applies only to cars you own outright.
Frequently asked questions
- When should I drop comprehensive and collision coverage?
- When the car's value falls under roughly ten times your deductible and the two lines exceed about 10% of that value yearly — here the binding floor sits near $5,000. Your $5,300 example sits just above it, squarely in judgment territory where expected recovery of about $130 argues loudly for dropping.
- What is the 10 times deductible rule for car insurance?
- A heuristic holding that physical-damage coverage stops making sense once the car is worth less than ten deductibles, because the maximum payout — value minus deductible — shrinks below a level worth insuring. With a $500 deductible that trigger sits near $5,000; with $1,000 deductibles, nearer $10,000.
- Is it better to have liability only on an old car?
- Financially, usually yes once value crosses under the crossover: the premium saved compounds every year while the most the coverage could pay keeps shrinking. Keep liability limits robust regardless — injury claims, not your own bumper, are what bankrupt households after accidents.
- How much is full coverage on a $5,000 car?
- Physical-damage lines commonly run $600-$1,000 a year even on old vehicles because rating keys off driver record and location more than car age. That density — often 15-20% of the car's value annually — is exactly what pushes older cars over the drop threshold.
- Can I drop full coverage if my car is financed?
- No — lenders require comprehensive and collision until the lien releases, and force-placed coverage they buy instead costs far more while protecting only them. Once the loan clears or the payoff falls near the car's value, this crossover becomes yours to decide.