The pricing tradeoff in insurance design
Insurance policies always offer a choice between a higher premium (lower out-of-pocket cost upfront) or a lower premium (higher out-of-pocket cost when a claim occurs). A high deductible shifts more risk to you, so insurers charge a lower premium in return. A low deductible shifts more risk to the insurer, so they charge a higher premium.
The total expected cost depends on two factors: the probability that you will file a claim, and the magnitude of a typical claim. If claims are rare, the lower premium from a high deductible saves money in total. If claims are frequent, the higher deductible adds up quickly and the low-deductible option costs less overall.
Choosing the right deductible for your situation
Auto insurance deductibles commonly range from $250 to $2000. A 16-year-old driver with a new car should choose a low deductible because accidents are likely. A 55-year-old with a 10-year-old car and a clean history should choose a high deductible because accidents are rare and the premium savings compound over 20+ years of safe driving.
Personal financial reserves matter too. If an unexpected claim would strain your budget, a lower deductible protects your cash flow. If you have an emergency fund, a higher deductible is mathematically smarter.