Americans who take part in vision insurance plans are twice as likely to schedule an eye exam as those who don’t. — Photo by Southern Stock Corp/Corbis

En español | Getting a comprehensive eye exam and new frames and lenses can mean some serious sticker shock: Health insurance policies generally cover eye care only if you’ve got a medical issue. So many Americans seek to soften the cost by signing up for vision plans, either through their employers or on their own.

See also: Save up to 30% on eye care and eyewear.

Here are nine things to keep in mind when you consider what type of plan — or no plan at all — is best for you.

1.  There are two basic types of plans. Vision benefits packages give you access to a fixed dollar amount of services for a premium or a membership fee. Discount vision plans simply give you a predefined discount, such as 20 percent off covered services, to whatever level of spending you want.

2.  Benefits packages function like health insurance. You might have a co-pay of $10 to $25, and the plan typically limits what it will shell out for specific products or services. For example, the plan might provide for a fixed dollar amount toward a pair of frames and require you to pay the difference if you choose a more expensive pair. Elective services such as LASIK eye surgery are typically not covered.

3.  Benefits packages tend to charge you more than discount plans. According to AllAboutVision.com, a website that provides eye health information, a typical annual premium for a benefits package for an individual is $170.95 compared with $69.50 for a discount vision plan.

4.  If you aren’t planning to get new glasses or don’t make use of many vision services each year, a discount plan may be the best route, says Mary Carder, president of EyeBenefits, a discount plan provider based in  Scottsdale, Ariz.

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