Committing to the care of a pet over its lifetime has substantial emotional rewards. Unfortunately, it can also carry the occasional financial penalty. Depending on the diagnosis, some individuals can spend upwards of $30,000 out of pocket on medical care for a four-legged loved one. In fact, Fortune reports that pet owners in the U.S. are expected to shell out a total of $15.9 billion this year on veterinary care, according to the American Pet Product Association.

Despite rising veterinary costs, less than 1 percent of the nation’s 174 million dogs and cats are covered by some kind of pet health insurance. If you’re on the fence about signing up, here are a few things you should know.

Health insurance for pets generally mirrors the same policies as bipedal human coverage. There’s typically a deductible, co-pays, and a monthly premium that can be as little as $25, with the cost increasing for more comprehensive plans. (The higher the premium, the more the insurance is likely to pay out, with some options covering up to 100 percent of incurred expenses.)

For a relatively healthy animal, it’s likely that the premiums will outpace any needed veterinary care. But if your pet should be struck with any number of complicated issues—cancer, heart trouble, accidents, or long-term monitoring—the bills can quickly add up into the thousands. Even a moderate policy would help offset some of those costs.

Naturally, insurance companies aren’t in the habit of being generous, which is why reading the fine print is crucial. Some policies won’t cover certain breeds due to chronic health issues or pre-existing conditions like hip dysplasia; others may insist on the insured paying the veterinarian and then waiting for reimbursement.

If you can afford a surprise bill, you may have trouble justifying the expense. But if a lump sum would be hard to come by, you might be best off having some form of coverage. In either case, preventative medicine is a must: Routine health care like brushing a pet’s teeth or making sure they’re spayed or neutered can help offset future complications. (Tooth plaque can lead to lung issues; spaying can reduce the incidence of tumors.) It’s also a good idea to watch your pet’s weight. The thinner they are, the fatter your wallet is likely to be.

[h/t Fortune]

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