Most dog owners don't have thousands of dollars sitting around to cover surgery or cancer treatment. That is where pet insurance comes in. Policies typically reimburse 70% to 90% of covered costs related to illness and injury.

Having that coverage allows you to make decisions about your pet's care based on its well-being, not your wallet.

"In my experience, when pet owners say they're covered by insurance, it takes the emotional angst out of the equation," said Barry Kipperman, a veterinary specialist in internal medicine.

Here is what you need to know when shopping for a pet policy.

You still pay out of pocket. Unlike human health insurance, most pet insurance policies reimburse you rather than pay the bill upfront. So you pay for the treatment, submit the claim and receive a check for the covered portion.

Vaccinations, flea and tick treatments and annual exams are all expected parts of pet ownership. But this type of routine care is not covered by most pet insurance policies. Some providers offer it as an upgrade or add-on. Do the math to make sure it's worth the added cost.

Office-visit charges usually aren't included. If your dog is sick or injured, your policy will likely cover diagnostic tests, such as blood work and X-rays, and any prescribed medication. But most policies don't cover the visit itself. A handful of providers, including Figo and Pets Best, include exam fees in some or all of their policies.

Most policies have a waiting period, so your pup typically isn't covered the day you enroll. And there may be different gaps for different types of coverage or conditions.

There are a few things you want to make sure you are covered for, said Nicole Ellis, a certified professional dog trainer with Rover, a pet-care app.

Cancer. Arthritis. Allergies. Kidney disease. These are not short-term conditions, and treatment can last for the life of your pet. You want to ensure you are covered for the duration of the condition.

Some breeds are prone to certain issues — Great Danes and boxers are prone to heart disease, for example, and pugs, Shih Tzus and other smushed-faced dogs often have breathing issues. Research any breed-specific ailments and make sure they are covered by your policy before you enroll.

The medical care available for dogs now rivals that of humans, including services like acupuncture and chiropractic care. If you want the full range of options, make sure these alternative treatments are covered by your plan.

Annual deductibles are standard for human health insurance, but the same isn't true for pet policies. With some companies, the deductible is per incident or condition.

So if your dog sprains a knee, you pay one deductible and any subsequent care related to that issue is covered. But if your pup has a different issue you have to pay another deductible.

There are benefits to incident deductibles, though, noted Carol Edwards, executive director of Early Alert Canines, which trains medical alert dogs for insulin-dependent diabetics.

Insurance covered 90% of the costs, minus a $1,000 deductible, when Edwards' black Lab went through cancer treatment. "Years later, his cancer came back," Edwards said. "Since the deductible was already paid, his follow-up care was covered."

Kelsey Sheehy is a writer at NerdWallet. E-mail: