Do emergency braking and blind-spot alerts cut insurance claims?

Yes, the loss data show that automatic emergency braking and blind-spot warning reduce insurance claims, and the biggest drops come in claims for damage and injuries the equipped driver causes to other people. The drop in claims for the equipped car's own damage is much smaller, because the sensors that prevent some crashes are expensive to replace in the crashes that still happen. That tug of war is also why a separate "safety feature discount" is not a given when you buy a car that has these systems.

The most complete public summary is the Highway Loss Data Institute's April 2023 compendium of collision avoidance research, which pools results from studies of 11 makes. Everything in this article about percentages comes from that document unless another source is named.

How researchers measure what one feature does

The Highway Loss Data Institute (HLDI) is the insurance-industry-funded research group that sits beside the Insurance Institute for Highway Safety (IIHS). It does not guess at a feature's value. It takes insurance claim records and asks whether cars with a feature file fewer or smaller claims than otherwise similar cars without it.

Many of these features were optional extras, so one model year can contain both equipped and unequipped cars, and buyers who pay for options may not drive like buyers who skip them.

HLDI's approach, as described in its April 2023 bulletin, works like this:

1. Identify which cars have the feature. Manufacturers supplied lists of vehicle identification numbers (VINs) showing which cars carried which technology. For some Honda and Subaru models the trim and equipment can be read from the first 10 positions of the VIN.
2. Compare within one model. A regression analysis compares equipped and unequipped cars of the same make, series and model year, so that a redesign between model years does not get credited to the feature.
3. Control for everything else it can. The models adjust for calendar year, garaging state, vehicle density, the rated driver's age, gender and marital status, the collision deductible and the driver's risk class. They also account for other safety systems on the same car, so that a forward-collision result is not really a blind-spot result.
4. Measure frequency and severity separately. Claim frequency is claims per insured vehicle year. Claim severity is the average payment per claim. Multiplying the two gives overall losses.
5. Run it by coverage. Each coverage answers a different question, which matters below.

Some features cannot be separated. Blind-spot warning on many cars comes bundled with rear cross-traffic alert, and forward-collision warning often comes with lane departure warning or adaptive cruise control. HLDI notes each such bundle in its tables and judges which feature probably drives the result.

A caution about the model years: the compendium combines manufacturer-by-manufacturer studies rather than one fixed window. The titles of the underlying bulletins give a sense of the range, for example Audi 2010-17, Mazda 2007-17, Volvo 2007-10, BMW 2013-17, Honda Accord 2013-15, Honda Odyssey 2011-17, Subaru 2013-21 and Nissan Rogue 2017-19. Early systems were cruder than what ships today, so treat the percentages as direction and rough size, not a promise about your car.

Why the answer depends on the coverage

HLDI separates the coverages because each pays for something different. In its definitions, collision coverage pays for damage to an at-fault driver's own vehicle, property damage liability pays for damage the at-fault driver does to other people's vehicles and property, and bodily injury liability pays for injuries the at-fault driver causes to people in other vehicles or on the road. Medical payments (MedPay) and personal injury protection (PIP) cover the occupants of the insured car.

A system that stops you from rear-ending the car ahead helps on three of those lines at once. Your own bumper survives (collision), the other driver's bumper survives (property damage liability), and nobody in the other car gets a neck injury (bodily injury liability). But the amount saved on each line is different, because the typical claim on each line is different, which is why one number for "claims" hides the story.

What the studies found, feature by feature

The table gives HLDI's combined estimates for the change in claim frequency associated with each feature, compared with similar cars without it. A negative number is a reduction. "Not significant" means the confidence interval included zero, so the result could be chance.

Source: HLDI Bulletin Vol. 40, No. 4, April 2023. Unless marked, every figure is statistically significant.

Several patterns stand out.

• Systems that act beat systems that warn. Front AEB, which brakes for the driver, cut property damage liability claims by 14.4% and bodily injury claims by 23.6%. Forward collision warning alone, which relies on the driver reacting, cut them by 9.0% and 17.3%. HLDI's discussion makes the same comparison.
• Injury claims fall more than damage claims. With front AEB, the injury figure is larger than the damage figure. A plausible reason is that even when braking does not prevent the crash, it lowers the speed at impact, which matters more for injuries than for dented bumpers. IIHS's own police-report research found larger reductions in rear-end crashes involving injury than in rear-end crashes of all severities, according to its driver assistance page.
• Lane departure warning barely shows up. HLDI found no significant effect on claims. IIHS research on police-reported crashes did find fewer single-vehicle, sideswipe and head-on crashes with the feature, but those crash types are rarer and often more severe than the fender-benders that dominate claim counts.
• Rear automatic braking has the largest property damage effect, because backing crashes are frequent, low-speed and cheap, which is exactly the kind of claim a system can erase. Collision frequency moves least of all, in the low single digits for most features.

On the IIHS side, its summary reports that forward collision warning with automatic braking cut rear-end crashes by about half in police-reported data, and blind-spot detection cut lane-change crashes by 14%. Those are crash rates, not claims, but they point the same way as the HLDI claim data.

Why do the percentages look small? Most claims are small. HLDI's figures for calendar year 2021 show that nearly 50% of collision claims cost under $3,000, and the most common size for collision and property damage claims is $1,000 to $1,999. A system built to stop crashes at highway speed does little about the shopping-center scrape that makes up a large share of claims. For more on reading these bulletins yourself, see How to read a Highway Loss Data Institute loss bulletin.

Why repair severity can rise

Frequency is half the picture. The other half is what each remaining claim costs. HLDI found that two of the features raised the average collision claim even as they lowered the number of claims:

• Forward collision warning was associated with a 2.1% increase in collision claim severity.
• Curve-adaptive headlights were associated with a 4.3% increase.
• Front AEB showed no significant change in severity on average.

The mechanism is location. The front of a car is where many crashes land, and that is where radar units, headlight assemblies and some cameras sit. HLDI points to a Honda Accord comparison: a version with a radar unit in the front bumper had higher collision severity, while one with a camera mounted behind the windshield did not. HLDI noted that a windshield-mounted camera is better protected and would likely be covered under comprehensive rather than collision if the glass breaks. On curve-adaptive headlights, HLDI cited a parts price from Audatex Estimating (2018): the 2017 Subaru Outback's steering-responsive xenon headlamp assembly listed at $657 against $355 for the ordinary halogen assembly.

The cost of the hardware itself is documented by AAA. In a December 2023 fact sheet based on a 2023 Ford F-150, Nissan Rogue and Toyota Camry, AAA put the cost of repairing or replacing damaged ADAS parts at:

AAA stresses that these figures exclude body work and other collision repairs. Recalibration after a repair is a separate step that shops must perform and document; see ADAS calibration and the guide driver-assistance sensors and the cost of repairs.

The net effect for the equipped driver's own damage claims is small either way. HLDI's combined estimates show overall collision losses (frequency times severity) down 1.3% for forward collision warning, down 3.0% for front AEB, and up 2.9% for curve-adaptive headlights. So fewer crashes do not always mean less money paid on collision, and for one feature the money went the other way.

A worked example with invented numbers

These numbers are hypothetical, built only to show how frequency and severity combine. They are not market data. Take 1,000 identical insured cars without a feature, with 50 collision claims a year averaging $5,000.

The headlights prevent 0.7 claims per thousand cars, but each of the remaining 49.3 costs $215 more. The sum rises roughly 3%, close to HLDI's 2.9% finding. Now apply the same logic to liability on the same invented fleet: 20 property damage liability claims averaging $4,000 is $80,000. Front AEB takes frequency down 14.4%, to 17.1 claims, and the total to about $68,500, a drop of more than $11,000 per thousand cars. Liability claims are paid for damage to someone else's property, so the sensors on your own bumper are not part of that bill.

That asymmetry is the heart of the matter. The savings from the feature accrue mostly on liability coverage, where repair costs of the equipped car do not enter, while the extra costs accrue on collision and comprehensive coverage, where they do.

Why insurers rarely price a feature on its own

Buyers are often told that safety technology lowers premiums. Whether it does depends on how the insurer rates the car.

For collision and comprehensive, the usual route is the vehicle rating symbol. The New York Department of Financial Services explains on its page on physical damage premiums that these premiums track the estimated cost of future claims for damage to or loss of the vehicle, and that repair cost, theft record and the damage a model tends to suffer in a crash all feed in. It adds that the Insurance Services Office (ISO) rating symbol program moved in 2011 from 27 symbols to 75 and introduced separate symbols for collision and comprehensive, with higher symbols meaning higher claim cost. The symbol follows the make, model and model year, so a car's actual loss experience, including whatever its sensors do to claims and repairs, ends up inside the symbol. A separate line item for "has automatic braking" would double count what the symbol already captures. See vehicle symbol and how a redesign changes a car's insurance rating group and your premium.

Liability coverage works differently in many states. ISO has also published make-and-model symbols for liability and for no-fault and medical payments coverages; the program was introduced in 2004 and was filed as an alternative rating program in most states, according to Insurance Journal's report at the time. Whether your insurer uses it, or its own variant, is a company decision filed with the state.

A second reason is saturation. HLDI estimated that front crash prevention was standard or optional on 89% of 2021 model year vehicles but was on only 36% of all registered vehicles in 2021. As the feature becomes standard across a model line, there is no unequipped group to discount against, and the effect is simply baked into the base rate.

Some insurers do list discounts for vehicle safety or driver-assistance features, and some states mandate certain ones. Florida requires discounts for factory anti-lock brakes and airbags but does not set percentages, and the guide safety feature and anti-theft discounts covers what is common. If your insurer lists one, it will say which features qualify and which coverages the discount touches. Do not assume it exists; ask.

How driver behavior and switched-off systems dilute the effect

A feature that is turned off prevents nothing. IIHS checked about 2,400 vehicles brought in for service in the Washington, D.C. area and reported in October 2024 that lane departure warning or prevention was switched on in 87%, compared with 51% in a similar study eight years earlier. Front crash prevention was active in 96%, against 93% before, and in many designs it cannot be switched off at all. IIHS credited better designs and settings that are harder to disable.

The effect also varies with who is behind the wheel. HLDI cites a study of Honda Accord forward collision and lane departure systems that found a 17% drop in property damage liability frequency for rated drivers 24 and younger, 12% for ages 25 to 64 and 3% for 65 and older. The systems help most where drivers crash most, so a pooled average understates the benefit for some households and overstates it for others.

There is also a fleet effect. HLDI points out that even sizeable reductions have only a minimal impact on all crashes as long as most cars on the road lack the feature; claims across the whole fleet fall as equipped cars replace older ones. It estimated front AEB would rise from 18% of registered vehicles in 2021 to 43% by 2026, partly because of a voluntary commitment by automakers, brokered by IIHS and NHTSA, to put it on at least 95% of their vehicles. In May 2024 NHTSA published a final rule for a new standard requiring automatic emergency braking, including pedestrian detection, on light vehicles; check NHTSA for the current compliance schedule, which is outside this article.

What this means when choosing a car

Insurance cost should not be the main reason to pick or skip a safety feature; the crash you avoid is worth more than the premium difference. If cost is on your list, this routine follows from the data.

1. Treat automatic braking as the feature with the best claims evidence, then blind-spot warning. Lane departure warning has the weakest claims evidence.
2. Get quotes on specific trims by VIN, not just by model. The insurer decodes the VIN and applies the symbol for that exact configuration.
3. Ask where the sensors sit. A forward camera behind the windshield and a radar unit in the bumper cost differently to fix and are covered differently, the glass often under comprehensive.
4. Check glass coverage. If the windshield carries the camera, a replacement means recalibration. Ask whether your glass deductible applies and whether calibration is included. See full glass coverage.
5. Keep the systems on unless a specific setting is causing a problem you can fix with the manufacturer.
6. After any front-end repair, ask for the calibration record. AAA's fact sheet recommends requesting proof that safety systems were repaired and calibrated.

Questions to put to an insurer or agent:

• "Does my quote reflect this exact trim and its driver-assistance package?"
• "Do you offer a discount for automatic braking or other crash-avoidance features, and on which coverages?"
• "Is a camera or radar replacement paid under comprehensive, collision or glass coverage?"
• "Does a repair include calibration, and is it part of the estimate?"

Rules and programs differ by insurer and state. Your state insurance department can tell you which discounts are mandatory where you live, and the state car insurance requirements lookup tool shows the basics for your state.

Common questions

Will a car with automatic braking always cost less to insure?

No. The rating symbol blends expected claims and repair costs, so a car that prevents crashes but costs a lot to repair can land at a similar price to a car without the feature. Other factors, including your driving record, ZIP code and the coverages you choose, usually outweigh any feature.

Does the insurer know my car has the feature?

Usually yes, through the VIN. HLDI itself relied on VIN lists supplied by manufacturers to classify cars, and insurers decode a VIN to retrieve the equipment, trim and rating symbol. If your quote used the wrong trim, tell the insurer; it can change the result.

Do these features lower my own collision claims much?

A little. HLDI's combined estimates for the equipped driver's collision frequency are in the low single digits, and for some features the repair-cost increase offsets the benefit. The larger effects appear on liability claims, which is money paid to other people.

Are the results out of date for new cars?

Partly. The underlying studies cover vehicles from roughly 2007 to 2021 model years, and systems have improved since. HLDI itself said future analyses would revisit combinations such as blind-spot warning paired with rear cross-traffic alert and that lane-keeping assist may outperform warning-only lane departure systems. Expect the figures to be revised as newer cars accumulate claims.

Key takeaways

• HLDI's pooled loss data show forward collision warning, front automatic braking and blind-spot warning reduce claims, with the largest cuts in property damage and injury claims paid to other people.
• Systems that brake automatically outperform systems that only warn, and lane departure warning shows little effect on insurance claims.
• Sensors in bumpers, grilles and headlights can raise the cost of the crashes that still happen, so collision savings are small and one feature (curve-adaptive headlights) raised overall collision losses.
• A separate discount is not guaranteed because rating symbols already reflect each model's claims and repair history; ask the insurer which features it credits.
• Features only help while switched on and working, so keep them enabled and insist on calibration after front-end repairs.