Insurance Curator Customizing your car adds personality and performance — but it also raises important insurance questions. In the United States, standard auto policies usually cover damage to the vehicle but often exclude or limit coverage for aftermarket parts, custom accessories, and performance modifications unless you add specific endorsements or choose a specialty insurer. This guide explains coverage options, typical costs, and steps to protect modified vehicles in major U.S. markets (Los Angeles, Houston, and Miami), with real providers and price ranges to help you shop smart.
Why standard policies may not protect custom parts
- Standard collision and comprehensive cover damage to your car, but they typically reimburse based on actual cash value (ACV) for the vehicle as-is — excluding added aftermarket value unless endorsed.
- Aftermarket parts (audio systems, turbo kits, lifted suspensions, custom wheels) may be explicitly excluded or only partially covered.
- Failure to declare modifications can result in denied claims or policy cancellation.
Authoritative resources: Insure.com and insurer pages explain that modifications need to be declared and often require extra coverage. See:
- Insure.com — How to insure a modified car: https://www.insure.com/car-insurance/modified-cars.html
- Progressive — Custom parts & equipment help: https://www.progressive.com/answers/custom-parts/
Coverage options for modified cars (what to consider)
1. Custom Parts & Equipment (CPE) endorsement
- Purpose: Adds coverage specifically for aftermarket parts and non-factory equipment.
- Typical coverage: Covers loss, theft, or damage up to a declared dollar limit.
- Cost: Commonly $50–$500/year depending on declared parts value and location.
- Best when: You have moderate-value mods (audio upgrades, wheels, cosmetic kits).
2. Agreed-value / agreed amount policy
- Purpose: Insurer agrees in advance on vehicle value including mods. If total loss occurs, you receive the pre-agreed amount.
- Best when: High-value, extensively modified vehicles (race cars, show cars).
- Common providers: Specialty insurers and classic-car insurers offer this option. See the classic-car coverage primer: Best Insurance For Classic Cars: Agreed Value, Storage and Show Coverage Explained.
3. Scheduled personal property / floater
- Purpose: Schedules and insures specific high-value items (aftermarket engine, ECU, artwork, stereo).
- Cost: Often a small percentage of item value annually (e.g., 1–5% of declared value/year).
- Best when: You have a few high-value add-ons rather than many small parts.
4. Specialty modified-car insurers
- Purpose: Insurers who specialize in modified, performance, or custom vehicles will underwrite mods as standard.
- Example providers: Some regional and niche insurers, plus mainstream carriers with endorsements (GEICO, Progressive, State Farm, USAA).
- Consider: Coverage forms vary; compare limits, deductibles, and exclusions.
How insurers set premium increases for mods
Premium impact depends on:
- Value of the modifications (higher added value → higher endorsement cost).
- Type of modification (safety upgrades may reduce rates; performance mods that increase speed can raise them).
- Use-case (track use often excluded unless separately insured).
- Driver profile and location (urban areas with higher theft/collision rates increase cost).
Typical impact ranges:
- Minor cosmetic mods: $0–$150/year.
- Moderate performance or electronics: $100–$400/year.
- Major engine, turbo, or full-custom builds: $300–$1,500+/year (may require agreed-value or specialty policy).
Sources on typical costs and endorsement practices: Insure.com and Progressive explain endorsement availability and variability:
- Insure.com — https://www.insure.com/car-insurance/modified-cars.html
- Progressive CPE info — https://www.progressive.com/answers/custom-parts/
Real-company examples & sample pricing (Los Angeles, Houston, Miami)
Note: Exact quotes depend on vehicle, driver history, and declared accessories. Below are representative ranges and guidance based on insurer offerings and market trends for 2024–2025:
-
Progressive
- Offers a Custom Parts & Equipment endorsement; cost varies by declared value.
- Estimated pricing: $100–$400/year for $1,000–$10,000 in aftermarket parts (depending on location and risk).
- Info: https://www.progressive.com/answers/custom-parts/
-
GEICO
- Provides coverage options for custom components through endorsements and claims handling for mods when declared.
- Estimated pricing: $75–$350/year for common aftermarket packages.
- Info: https://www.geico.com/information/insurance-basics/auto/custom-parts/
-
State Farm
- Offers endorsements and may allow scheduling of custom parts; cost similar to national peers.
- Estimated pricing: $80–$450/year based on declared parts/value.
-
USAA
- USAA has tailored options for members with aftermarket gear; pricing competitive but membership-restricted.
- Estimated pricing: $50–$300/year for modest mod packages.
City-specific considerations:
- Los Angeles (California): higher theft and accident exposure in metro areas can push costs up. Expect endorsements on high-value audio/performance parts to lean toward the higher end of ranges above.
- Houston (Texas): flood/vehicle damage risk in certain ZIP codes may increase comprehensive rates; disclose mods to avoid gaps.
- Miami (Florida): very high theft and total-loss rates increase both base premiums and endorsement costs — plan for endowment costs on the high end.
For shopping across providers and understanding rate differences by state/city, see: Best Insurance For Cars Across States: How Rates and Requirements Differ and How to Shop.
How to shop and document your mods (step-by-step)
- Inventory every modification:
- Photos (installed and close-ups), receipts, invoices, and serial numbers.
- Get written appraisals for high-value parts.
- Call insurers before installing major mods to confirm coverage terms and premiums.
- Compare:
- CPE endorsement limits and caps
- Deductible options
- Whether mechanical failures from mods are excluded
- Consider specialty insurers or agreed-value coverage for extensive builds.
- Keep all records and file endorsements promptly to avoid claim denials.
Useful comparison: Best Insurance For Cars by Provider: Comparing GEICO, State Farm, Progressive and USAA
Coverage comparison table
| Coverage type | What it covers | Typical annual cost (U.S.) | Best for |
|---|---|---|---|
| Standard collision & comprehensive | Damage to vehicle (ACV basis) — usually excludes aftermarket value | Included in policy; no extra unless you add limits | Stock cars or small, inexpensive mods |
| Custom Parts & Equipment endorsement (CPE) | Declared aftermarket parts up to limit | $50–$500+ | Multiple aftermarket parts or moderate-value upgrades |
| Scheduled personal property / floater | Specific high-value items listed individually | ~1–5% of declared value/year | High-end audio, ECU, or rare parts |
| Agreed-value policy | Pre-agreed total vehicle value including mods | Higher premium; depends on agreed value | Show cars, extensive custom builds |
| Specialty modified-car insurer | Tailored policies with mods built-in | Varies; sometimes premium similar to agreed-value | Track, race, or heavily modified vehicles |
Common exclusions & red flags
- Track use and racing are often excluded.
- Modifications made after a loss but before claim filing may be denied.
- Failure to declare high-value mods can lead to claim denial or policy cancellation.
- Mechanical breakdown of aftermarket parts often not covered — consider a mechanical protection plan if applicable.
Quick checklist before you modify
- Get insurer pre-approval for major performance upgrades.
- Keep purchase invoices and install receipts.
- Photograph installations and log serial numbers.
- Ask about agreed-value options for show-quality builds.
- Compare endorsements across at least three insurers and get written policy language.
Further reading and related resources
- Best Insurance For Cars: Complete Guide to Choosing Between Full Coverage and Liability: https://insurancecurator.com/best-insurance-for-cars-complete-guide-to-choosing-between-full-coverage-and-liability/
- Best Insurance For Classic Cars: Agreed Value, Storage and Show Coverage Explained: https://insurancecurator.com/best-insurance-for-classic-cars-agreed-value-storage-and-show-coverage-explained/
- Best Insurance For Cars by Provider: Comparing GEICO, State Farm, Progressive and USAA: https://insurancecurator.com/best-insurance-for-cars-by-provider-comparing-geico-state-farm-progressive-and-usaa/
Authoritative external references:
- Insure.com — How to insure a modified car: https://www.insure.com/car-insurance/modified-cars.html
- Progressive — Custom parts & equipment information: https://www.progressive.com/answers/custom-parts/
- GEICO — Custom parts and equipment basics: https://www.geico.com/information/insurance-basics/auto/custom-parts/
If you own a modified vehicle in Los Angeles, Houston, Miami (or elsewhere in the U.S.), start by documenting your mods and calling your insurer for an endorsement quote — that single step can protect thousands of dollars of aftermarket investment and prevent claim headaches down the road.