Our surveys of consumers asking for ratings of vision centers reveal sizeable differences in customer satisfaction: Many outlets were were rated “superior” for “overall quality” by at least 90 percent of their surveyed customers, but others earned such favorable ratings from fewer than 50 percent.

Our Ratings Tables report results from our surveys of Consumers’ Checkbook subscribers and other other randomly selected consumers we invited to participate. The results are for companies that received 10 or more survey responses. For large chains, we also include scores that are pooled from ratings submitted by consumers in the seven metro areas where we publish Consumers’ Checkbook. Click here for more details on our customer survey and other research methods.

We found most eyewear customers were satisfied. When there are problems, complaints usually relate to second-rate customer service—rude salespeople, long waits, indifferent advice—and high prices.

But many things can go wrong when buying glasses: Lenses can be positioned wrong or be defective. Opticians and optometrists must understand complex matters, including matching your lenses to your eyes, fitting frames to your face (the contour of your nose is critical), and knowing what to recommend for people who need big corrections. They should also help you select specs that make you look spectacular with tips on flattering your eyes, your brows, and the shape of your face.

Contact lenses present their own set of issues. You’ll want good advice on the type of lenses that will suit your pattern of use and your budget. And you’ll want proper follow-up when you get a new type of lens, to ensure that it presents no risk to your eyes’ health.

If you have a prescription from a recent exam, you can go to any optician or optometrist for eyeglasses. Many of them also sell contacts, and most will dispense them based on a recent prescription you’ve obtained elsewhere, but some insist on performing their own exam. Most suppliers consider a prescription recent enough if the exam took place within the past year, but some accept even older prescriptions, particularly for eyeglasses, depending on your age and eye-care history.

If you don’t have a current prescription, you can get one from an optometrist or ophthalmologist. Opticians can’t perform eye exams, but many vision centers either are operated by optometrists, who can, or have an optometrist working in an affiliated office. (California law prohibits opticians from employing optometrists, but the optometrist may be located just one door away.)

Once you get a vision test, you have the right to take your prescription for glasses or contacts anywhere else to buy them. Under federal law, after completing an eye exam that includes a refraction (vision test), an ophthalmologist or optometrist must provide the patient with a copy of their prescription for lenses, whether they ask for it or not.

Because you have the freedom to shop around, look for outlets that provide the best service. The ratings we collected from consumers indicate that customer service is a challenge for some eyewear outlets.

In general, chains and franchise operations received lower ratings than independents, but there was variation among chain and franchise operations. The chains or franchises with the lowest percentages of “superior” overall ratings, on average, were Target (54 percent), LensCrafters (57 percent), and For Eyes (58 percent); those with the highest percentages were Warby Parker (80 percent) and Costco (77 percent).

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