What is the 10% rule for collision and comprehensive?

Add up your annual collision and comprehensive premiums, then compare that to your car's value minus your deductible, the most a claim could ever pay you. If the yearly premium is more than about 10% of that payout, the coverage is a poor deal and worth dropping. Below 10%, it usually still pays to keep it.

What does 'full coverage' actually mean?

It's not an official policy type. It just means liability plus collision plus comprehensive. Liability is required and protects other people; collision and comprehensive are optional and protect your own car. Dropping the optional two is what people mean by going to 'liability-only.'

Will my lender let me drop collision and comprehensive?

Not while you have a loan or lease. Lenders require collision and comprehensive to protect their stake in the car until it's paid off. Once you own the car outright, the decision is yours, which is often right about when the 10% math starts favoring dropping them.

Should I raise my deductible instead of dropping coverage?

On a car that's still worth insuring, raising the deductible is a good middle step: it lowers the premium in exchange for self-insuring the first slice of a claim, and only makes sense if you keep enough cash to pay that deductible. On a car that fails the 10% test, dropping the coverage entirely usually beats tweaking the deductible.

When to drop collision and comprehensive coverage: the 10% rule

Collision and comprehensive are worth real money on a newer car and a bad deal on an old one. Here's the simple math that tells you exactly when to drop them and pocket the premium instead.

In short

Drop collision and comprehensive when their combined annual premium climbs above about 10% of your car's value minus your deductible, the most a claim could ever pay you. On a newer car that payout is large and the coverage is a good deal; as the car ages and its value falls toward the premium, the math flips and you're paying more each year than the coverage can realistically return. Liability and uninsured-motorist coverage stay regardless: those protect other people and your medical costs, not the car's sheet metal. Run the exact numbers for your vehicle.

"Full coverage" is one of the most misleading phrases in car insurance. It isn't a special tier of protection. It just means you've stacked three coverages together: liability (required, protects other people), plus collision and comprehensive (optional, protect your own car). The optional two are where a lot of money quietly leaks out, because people keep paying for them long after the car is worth insuring. There's a simple rule for knowing when to stop.

What collision and comprehensive actually do

Collision pays to repair or replace your car after a crash (you hit something, or something hits you) up to the car's value, minus your deductible.
Comprehensive covers the non-crash events: theft, fire, hail, flood, vandalism, a deer, a cracked windshield. Also capped at the car's value minus your deductible.

Notice the ceiling on both: they can never pay you more than what your car is worth. That single fact is what makes the drop-or-keep decision a math problem rather than a guess.

The 10% rule

Here's the whole method:

Add up your annual premium for collision and comprehensive (that portion of your bill, not the whole policy).
Find your car's actual cash value, roughly what it would sell for today.
Subtract your deductible from that value. This is the most a claim could ever pay you.
Divide the annual premium by that payout. If it's more than about 10%, drop the coverage.

Example: your car is worth $6,000, your deductible is $500, so the biggest possible payout is $5,500. If collision + comprehensive cost you $700 a year, that's 700 ÷ 5,500 ≈ 13%, above the threshold, so dropping them and banking the $700 is the better bet. If the same coverage cost $400, that's about 7%. Keep it.

The logic is straightforward: as a car ages, two things move in opposite directions. Its value (your maximum payout) falls, while the premium stays stubborn. At some crossover point you're paying so much each year, relative to the most you could ever collect, that self-insuring (banking the premium and accepting you'd absorb a total loss yourself) comes out ahead.

What you never drop

The 10% rule applies only to collision and comprehensive. These coverages stay no matter how old the car gets:

Liability: protects everyone else from you, and your entire net worth from a lawsuit. It's required, and it's the coverage you should carry more of, not less.
Uninsured/underinsured motorist: pays your costs when an at-fault driver has too little or no insurance.
Medical payments / PIP: covers injuries regardless of fault; required in no-fault states.

Dropping the car-repair coverages on an old beater is smart. Cutting your liability to save a few dollars is the opposite: that's the coverage standing between a bad crash and financial ruin.

The middle option: raise your deductible

If your car still passes the 10% test but the premium stings, raising the deductible is the intermediate move. A higher deductible lowers the premium because you're self-insuring the first slice of any claim. It only works if you actually keep enough cash to pay that deductible after a loss; otherwise you've traded a manageable bill for an unaffordable one at the worst moment.

Key takeaways

'Full coverage' just means liability plus collision plus comprehensive; the last two are optional.
Drop collision and comprehensive once their annual premium tops ~10% of car value minus deductible.
A lender or lessor requires them until the car is paid off; after that it's your call.
Never drop liability or uninsured-motorist coverage: those protect people and your assets, not the car.
Raising the deductible is a good middle step on a car still worth insuring.

The bottom line

Collision and comprehensive are genuinely worth it on a car with real value and a bad deal on one without. You don't have to guess which side of that line you're on: add up the premium, compare it to the most a claim could pay, and let the 10% rule make the call. On an aging car, dropping them and keeping the cash is often the single easiest way to cut your insurance bill without taking on any risk that matters.

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