Pet insurance companies advertise lifelong affordable medical coverage. But, as with any insurance, these policies typically pay out far less in benefits than what their customers pay for coverage. Before you buy, determine what you would do if your pet required expensive medical care. While many pet owners will pay anything to save their pets, others won’t. If you are in the latter group, pet insurance likely isn’t for you. If you belong to the pay-any-price group, consider purchasing insurance if hefty vet bills would strain your finances.

In the "Pet Insurance" section of our website, we detail results from our evaluations of 12 insurers. To assess value, we gathered premium and other out-of-pocket info, obtained price data showing what veterinarians charge for hundreds of services, and interviewed executives from leading insurers. We worked with the Purdue University College of Veterinary Medicine to develop a reasonable basket of vet services for our model pets: Woof, a medium-sized male mixed-breed dog; and Kitty, a male mixed-breed cat. We then conducted a cost/benefit analysis of each plan.

Here’s a summary of what we found:

Pet insurance isn’t cheap if you insure for life.

Pet insurance has improved over the last 20 years, in part due to new companies entering the marketplace. For many years, only a few companies offered coverage, and what they offered mostly covered medical care for injuries and low-cost illnesses, excluding care for congenital conditions, cancers, and other often expensive treatment.

But now that there’s more competition, pet insurance plans have greatly improved their coverage. The percentage of vets’ bills that get reimbursed is now typically 70 to 90 percent, and most plans no longer use set schedules of payments that could cap benefits at too-low levels, compared to what vets actually charge.

Other improvements: Pet insurance now commonly covers hereditary and congenital problems, chronic conditions, and alternative medicine such as acupuncture and chiropractic. Wellness and preventive care is available as an optional add-on for additional premiums. Consumers can usually customize their annual deductible, co-pay, and annual limits, and the internet makes buying a snap (though complete disclosure of how future premium costs will rise because of age is often lacking).

While insurance coverage and reimbursements have improved, out-of-pocket costs for pet owners typically have not, with premiums remaining the largest factor making pet insurance expensive.

For our sample pet, the total cost of premiums over a nearly 13-year lifetime for Woof ranged widely, with some insurers charging monthly premiums that added up to more than $30,000. Keep in mind those are just costs for buying insurance coverage; with most plans, policyholders must still contribute copays and deductibles, and not all costs are covered.

Murky marketing.

Most insurance plans tout affordability. And because most buyers sign up when their pets are young and monthly premiums are lowest, expenses seem manageable. But we found most insurers don’t adequately disclose that, starting around age four or five, pet premiums typically start to steeply rise—purely because the animals get older. Sooner or later, many plans’ premiums become unaffordable—some plans charge more than $2,000 per year to cover older animals. Meanwhile, comforting claims about benefits paid often mislead by omitting the considerable cost of premiums from the equation. If your pet has few medical problems, these premiums will seem especially pricey.

Insuring with even the better plans still usually increases total out-of-pocket costs.

If, over Woof’s lifetime, he suffered only moderate health problems (a total of $9,718 in vet bills for routine care, illness, and injury), the lowest-cost insurance plans still cost us more in premiums than they paid out in coverage. Our net out-of-pocket costs across all plans were thousands of dollars higher with pet insurance than without it.

We made the same conclusions when we analyzed all the pet insurance plans: If the pet needed only a low or moderate level of healthcare, it meant we’d pay far more in premiums than we’d get back in benefits.

Cats cost less.

The almost 13-year cost of premiums for Kitty were far lower than those for Woof. But, as with Woof, buying insurance for Kitty was unlikely to save us money over his life when he suffered only a low level of health problems—and careful, deliberative cats tend to have fewer vet bills than rambunctious dogs.

Wellness care coverage is a bad deal.

Much veterinary care consists of routine annual checkups, preventive care, and elective services not covered by accident and illness plans. You can typically add coverage for that, but it makes the total monthly premium so high that it’s better to just pay out of pocket.

Pet insurance is a good deal only if your pet suffers from many medical problems.

If Woof needed extensive care over his nearly 13-year life, we found most insurance plans paid out more than we paid in premiums, copays, deductibles, and for uncovered costs. But the odds of calamity are fairly low: We figured the chance of getting a vet bill of $1,000 or more is only about four percent per year. And because most pet insurance companies won’t cover preexisting conditions, you must purchase insurance before you discover medical conditions that are costly to treat.

Seek low-cost care.

Our undercover price shopping of area vet practices reveals costs vary widely depending on where you seek care. Using a low-cost practice gives you another reason to skip insurance, since you may pay lower out-of-pocket vet costs compared to pa

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