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CornerStone United Extended Warranty Reviews

Our team rated Cornerstone United Extended Warranty a 4.1 out of 5.0 stars in 2024 due to its reputation, coverage, cost, and customer experience.

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12/16/2023 09:08 PM

CornerStone United sets itself apart from the competition by covering multiple types of vehicles including RVs, powersports, and marine crafts. It also offers coverage for manufactured home structure and HVAC systems. Drivers can purchase these plans through dealerships and manufacturers, not directly from CornerStone United.

In this review, we’ll go through the extended warranty company’s strengths and weaknesses, so you’ll know what to do if you come across one of its plans at a dealership. Our team of experts has reviewed and ranked the best extended warranty companies in the industry. To find out what you’d pay for contract on your car, get free quotes from multiple reputable providers and compare coverage side by side.

Reputation: 4.5/5.0
Coverage: 5.0/5.0
Price: 4.5/5.0
Customer Experience: 4.5/5.0
idée Endurance is our first choice for extended warranties
  • Best Plan Offerings
  • Mileage Covered: 200,000 miles on the odometer
  • Free Cancellation: Full refund within 30 days
  • Plan Options: 6 different plans to choose from
  • Longest Plan Term: Up to 8 years
  • Discounts: $300 same-day signup discount, $250 shopping voucher, and others
Plan coverage includes Endurance Elite perks™
Exclusionary plan One-year membership for free
Powertrain plan Tire repair and replacement
Maintenance coverage with Endurance Advantage Key fob replacement
Roadside assistance Total loss protection
Towing Collision discount
Rental car $250 rewards voucher
Trip interruption coverage Endurance Protect app

CornerStone United Review: 4.1 Stars

CornerStone United offers a huge array of coverage plans for many different types of vehicles. However, many customers have had negative experiences with the company, so we rate CornerStone average compared to other extended warranty providers.

Review CategoryRatings Score
Customer Experience3.5
Overall Rating4.1

About CornerStone United

CornerStone United has been around for over 40 years, which is a long time for a warranty company. Its plans are available across all 50 states and also in Canada. As far as vehicles go, the company can cover cars that other providers wouldn’t necessarily cover. These include vehicles with many miles and modifications like lift kits or oversized tires.

CornerStone auto programs are backed by insurers that have an industry rating of “A-” or above. CornerStone United itself has an A+ rating from the Better Business Bureau (BBB), but it has an average customer rating with a number of negative reviews. If you’re looking for a good Acura extended warranty, there may be better options. But if you want to cover a boat or motorcycle, CornerStone could be a good choice.

CornerStone United Extended Warranty Coverage

CornerStone offers about a dozen different plans, and that doesn’t include optional add-ons or customization. Of course, not every vehicle will be eligible for every plan, but you’re certain to have a handful of options to choose from with CornerStone United.

CornerStone Auto

CornerStone’s standard vehicle service contract includes four coverage levels and five deductible options. Here are the facts:

  • Covers up to 200,000 miles for vehicles 19 years old or newer
  • Covers new vehicles up to 8 years/150,000 miles, with the option to add up to 4 years/50,000 miles afterward
  • Covers used vehicles up to 5 years/75,000 miles from current age and mileage
  • Options for commercial snowplows, lift kits, oversized tires, consequential damage, and mobility equipment

The four CornerStone United plan options are Powertrain (five systems covered), Basic (13 systems), Select (18 systems), and Ultimate (all parts except specified exclusions). Deductible options are $0, $50, $100, $200, or a disappearing $100 deductible.

Exclusions under Ultimate and other factory-like contracts include:

CornerStone Auto plans come with the following benefits:

  • Roadside assistance of up to $100 per occurrence
  • Rental car coverage of up to $200 per occurrence (additional $200 for major system repairs)
  • Trip interruption of up to $200 for food and lodging if 100 miles away from home after a breakdown

Xtended Auto

CornerStone United’s Xtended Auto plan is available for any age or mileage of vehicle. Drivers can customize coverage from basic powertrain to comprehensive component coverage. It’s a good option for cars that wouldn’t qualify for plans from other companies.

Extended Care

CornerStone Extended Care plans are available for vehicles that have up to 200,000 miles at the time of sale or are 20 years old or newer. The four coverage options are Engine & Transmission (four systems), Powertrain Plus (seven systems), Advantage (nine systems), and Supreme (12 systems).

The Supreme plan offers coverage on day one, while the other three require a waiting period of 30 days and 1,000 miles. Short-term contracts of three to six months also don’t have a waiting period.

Extended Care plans come with deductible options of $100 or $250. Benefits include rental car and towing reimbursement.

Limited Warranties

CornerStone United’s limited warranty program can extend factory warranties or provide original warranty coverage through manufacturers, dealers, and auction partners.

Tire And Wheel Protection

With these plans, drivers can protect tires and wheels from road hazard and cosmetic damage. Plans come in one- to five-year terms. They don’t require a deductible, and they can apply to vehicles up to 14 years/150,000 miles.

Road hazard damage is damage from metal, rocks, nails, potholes, screws, glass, and debris. The three plan options are:

  • Basic: Repairs or replaces damaged tires
  • Select: Repairs or replaces damaged tires and wheels
  • Ultimate: Expands coverage to include cosmetic damage and curb rash

Guaranteed Asset Protection (GAP)

This program covers the difference between your car’s actual value and the amount you have left on your loan if your vehicle is totaled. An upgraded option provides an additional $1,000 toward vehicle replacement.

Other Programs

CornerStone United offers the following plans for specialty vehicles:

  • Powersports: CornerStone can cover motorcycles, UTVs, ATVs, scooters, watercraft, snowmobiles, and jet boats. Benefits include rental units, pick-up service, and roadside assistance. GAP coverage and tire/wheel plans are also available for road motorcycles and scooters.
  • RV: Recreational vehicles up to 15 years old and with fewer than 100,000 miles are eligible for a variety of coverage plans. CornerStone covers anything from weekend campers to million-dollar motorhomes.
  • Marine: CornerStone covers new and used crafts that use either gasoline or diesel motors. Basic motors and drives are covered with optional accessory packages for anything from trailers to navigation.
  • Manufactured housing: CornerStone can cover structural items and a range of systems for manufactured homes. It’s one of the largest providers of manufactured home service contracts.

Cost Of A CornerStone United Extended Warranty

If your repair is covered, all you’ll have to pay is the deductible. But as for total warranty cost, that’s up to the selling dealer to decide. Dealers can price programs differently as long as they stay within a certain range, so you should be prepared to negotiate if you come across a CornerStone extended warranty.

The cost will be affected by the mileage, make, and model of your vehicle (or the vehicle you’re looking to buy). Coverage would cost more for a vehicle with higher mileage, since the likelihood of car repairs is also higher. Many things can impact the cost of your extended warranty, as seen in the graphic below.

Icons showing what factors affect extended warranty cost.

How CornerStone United Extended Warranties Work

Since CornerStone operates through dealers, manufacturers, and auction partners, there isn’t a quote form online. When you are presented with a CornerStone plan at a dealership, your only chance to buy it is when you buy the vehicle. Our recommendation is to read the entire customer contract and ask questions about the fine print before deciding.

CornerStone allows drivers to go to any licensed repair facility across the U.S. or Canada for coverage. The repair shop will need to be authorized before a repair can be made. You can get rental reimbursement only if the repair is covered by the contract.

Contracts are cancellable and transferable, but exact terms depend on the dealer that sold the plan.

CornerStone United Reviews

CornerStone United offers many different plans, but customer service is another story. Most online reviews are negative and mention how CornerStone refuses to honor claims. There are a few positive reviews, too. Here are a few examples:

“About four to five weeks after we left the dealer the engine blew up! Simply put, the company called it sudden failure after it was inspected. They paid the dealer and gave us a rental for five days. Her car runs perfect and all I had to do was pay a $100 deductible.”
– T.K., BBB

“After the inspection was done everything seemed fine until it was time for the part to be replaced. CornerStone refused to honor my warranty giving me different reasons every time.”
– John E., BBB

“I bought the top-of-the-line warranty. Every claim I have made was denied or reduced. So, in four years I have been reimbursed $36. That is $36 total, on a warranty I paid almost $5,000 for.”
– Chad W., BBB

Top Recommendations For Extended Car Warranties

The best way to shop for an extended warranty is to compare coverage from different providers. If you only get one quote, who’s to say whether it’s a good deal? Since prices are personalized, get quotes from multiple reputable companies to compare your options.

Endurance: 4.5 Stars

If you have a CornerStone plan, you’ll have to work with three different entities: the dealership, CornerStone, and the contract administrator. Endurance, on the other hand, cuts out the middlemen and administers its own plans as a direct provider. You won’t have to deal with a dealership because you can purchase an extended warranty directly from the company.

Endurance has been in business for more than 15 years. It offers six levels of protection from basic to factory-like coverage. The company has a rating of 3.7 stars from over 8,700 reviews on Trustpilot and offers a host of plan benefits including roadside assistance.

Get a free quote from Endurance to see how much you would pay for coverage.

CarShield: 4.3 Stars

If staying under budget is important to you, you should definitely check out CarShield. When we compared quotes from multiple providers, we found that CarShield offered the best monthly payment plans.

CarShield has been in business for more than 15 years and has been featured on ESPN, CNN, and HGTV. It offers six plans that can accommodate specialty vehicles like ATVs and motorcycles. CarShield is also the most popular provider we’ve reviewed. It has an impressive 4.2-star rating on Trustpilot from over 48,000 reviews.

Learn more about CarShield by getting a free quote for your vehicle.

How We Rate Warranty Providers

Our review process aims to deliver consistent and unbiased assessments of extended auto warranty providers. While there are multiple qualities that make a warranty company successful, our review team focuses on those we believe are the most important for consumers:

  • Reputation: It’s important that an extended car warranty company is able to meet its claims obligations. Companies with a strong rating from the Better Business Bureau (BBB) and a long history of reliable service score well in this category. We also evaluate the availability and transparency of each company’s contracts, as well as whether each provider offers a money-back guarantee.
  • Coverage: Our team of experts looks at the number of extended warranty plans available, as well as term limits, exclusions, and added benefits like roadside assistance. Ratings also take into account the availability of maintenance coverage.
  • Cost: Cost can be difficult to compare between providers because so many factors impact vehicle service contract pricing. To determine our cost score, we perform a secret shopper analysis for a variety of vehicles and plans and consider available deductibles.
  • Customer Experience: We listen to real customer sales calls and comb through reviews on sites like the BBB to learn about customer experiences. Warranty companies with a low volume of complaints score well in this area. We also consider the availability of mobile apps and chat features.

View Pricing from our #1 Provider – Endurance