What Is Considered Legally Blind? - GoodRx (2024)

About 1 million people in the U.S. are considered legally blind. Legal blindness is a term used by the U.S. government to determine eligibility for certain disability benefits and access to programs.

But the term doesn’t describe a person’s vision or how well they can complete their daily tasks. Each person’s experience will be different, even if they meet the criteria for this legal definition.

Here’s what it means to be legally blind and how it affects eligibility for certain programs and services.

What is legally blind?

Legal blindness in the U.S. is determined by a person’s visual acuity or visual field.

Because it’s a legal term, it has very exact definitions. A person is considered legally blind if:

• They have a corrected central visual acuity of 20/200 or worse in their better seeing eye, or

• They have a corrected visual field of 20 degrees or less in their better seeing eye.

Visual acuity describes someone’s central vision — what you see when you’re looking straight ahead. A visual acuity of 20/200 means that in a person’s better seeing eye, they need to be 20 feet away from an object to see it, while a person with 20/20 vision could see that same object at 200 feet away.

Picture the vision chart (Snellen chart) used by eye doctors. The “E” at the top corresponds to 20/200 vision. People who are legally blind cannot make out the letter E.

A visual field describes peripheral vision — what you see from the corner of your eye without moving your head. A person who’s legally blind may have very limited peripheral vision, sometimes called tunnel vision.

Keep in mind that people need to meet one of these criteria while wearing corrective lenses, like glasses or contact lenses. Many people who need corrective lenses meet the criteria for legal blindness when they’re not wearing their lenses.

In fact, if you have a glasses or contact lens prescription of -2.5 or more, then you have a visual acuity of 20/200. But you’re not considered legally blind because your vision improves with corrective lenses.

Does being legally blind mean you qualify for disability benefits?

Yes. If you’re legally blind you qualify for Social Security disability benefit programs through the Social Security Administration. People who are legally blind may be entitled to Social Security Disability Insurance (SSDI) and/or Supplemental Security Income (SSI). People can apply for these benefits on the Social Security Administration website or in person at their local Social Security Administration office.

In addition, people who are legally blind are entitled to additional benefits including:

• Rehabilitation services: These are therapies that help people with low vision learn to use their remaining vision to navigate their day-to-day activities. These therapies include working with eye doctors, low-vision specialists, and mobility specialists.

• Low-vision devices: These are devices that help people complete their day-to-day activities. They may include magnification devices, supplemental lighting, and other adaptive devices.

• Tax exemptions: This includes income and property tax exemptions.

• Education: Adaptive education resources are also available for adult learners and children.

What causes blindness?

There are many eye conditions that can lead to low vision and blindness. Common conditions include:

• Macular degeneration

• Cataracts

• Diabetic retinopathy

• Glaucoma

Each condition affects vision differently. For example, macular degeneration impacts a person’s central vision while glaucoma tends to affect peripheral vision. Cataracts affect both types of vision.

What does a legally blind person see?

It depends.

People who are not familiar with low vision tend to assume that people who are legally blind can’t see anything. But this isn’t the case at all. Only about 15% of people who are legally blind have no light perception, which means they can’t perceive any light or shapes.

Most people who are legally blind have some vision. And they can use that remaining vision along with adaptations to engage with their community and carry on their regular activities.

The underlying cause of a person’s low vision also plays a role in how someone navigates the world. For example, someone with macular degeneration has trouble seeing in dim environments. So having brighter lights can help them optimize their vision.

People with glaucoma develop peripheral vision loss, or tunnel vision so they can rely more on their central vision. But this can also vary from person to person.

“Glaucoma is a difficult disease for a patient to perceive,” says Dr. Erin Sieck, board-certified ophthalmologist and glaucoma specialist. “You could be legally blind from the disease due to lack of peripheral vision but still see 20/20 centrally. Oftentimes, even the central vision is dull and muted.”

A person with cataracts can notice generalized decreased vision. They may also develop severe glare symptoms making it difficult to see or drive at night. They may need to adjust their driving patterns so they’re not exposed to glare.