Social Security's Definition of Blindness

Social Security considers you blind if your vision is 20/200 or worse in your better eye with correction, or if your visual field is 20 degrees or narrower. This is the same standard the Internal Revenue Service uses for tax purposes. It does not matter whether your blindness is total or partial — what matters is the measurement in your better eye after you have worn glasses, contact lenses, or had surgery to correct it.

The Social Security Administration (SSA) measures blindness using visual acuity and visual field. Visual acuity is how clearly you can see at a standard distance. Visual field is how wide your side vision is — how much you can see to the left and right without moving your eyes. You must meet at least one of these two tests to be considered blind under Social Security rules.

If you are blind, you do not have to prove you cannot work. Social Security treats blindness as a presumptively disabling condition, meaning the agency assumes you cannot engage in substantial work activity. This is different from other medical conditions, where you must show both that you have the condition and that it prevents you from working.

Key Takeaways

  • Social Security defines blindness as vision of 20/200 or worse in your better eye with correction, or a visual field of 20 degrees or narrower.
  • The measurement must be taken after you have worn corrective lenses or had surgery — uncorrected vision does not count.
  • You do not have to prove you cannot work if you meet Social Security's blindness definition; the agency presumes you are disabled.
  • An eye doctor's report with specific measurements from a visual acuity test and visual field test is the document Social Security needs to evaluate your claim.
  • Blindness can be caused by many conditions — cataracts, glaucoma, diabetic retinopathy, macular degeneration, retinitis pigmentosa — but only the measurement matters for SSDI purposes.

Visual Acuity: The 20/200 Standard

Visual acuity is measured using an eye chart, usually the Snellen chart, where you read letters from a distance of 20 feet. A measurement of 20/200 means you must stand 20 feet away to see what a person with normal vision can see from 200 feet away. If your vision is 20/200 or worse in your better eye even with glasses or contacts, you meet this part of Social Security's blindness definition.

The key word is "with correction." Social Security does not care if you are legally blind without glasses. If corrective lenses bring your vision to 20/100 or better, you do not meet the acuity standard, even if you cannot see without them. The agency measures what you can see after you have done everything available to improve your vision.

Some people have vision worse than 20/200 but still have useful sight — they can navigate, recognize faces, or read large print. Social Security does not distinguish between these cases. If the measurement is 20/200 or worse, you meet the acuity test.

Visual Field: The 20-Degree Test

Visual field is the total area you can see when looking straight ahead without moving your eyes. A normal visual field is about 180 degrees — roughly 90 degrees to each side of center. Social Security's blindness definition includes people whose visual field is 20 degrees or narrower in their better eye, even if their central vision (visual acuity) is better than 20/200.

This test catches conditions that narrow your peripheral vision dramatically. Retinitis pigmentosa, for example, can leave a person with good central vision but almost no side vision — sometimes described as "tunnel vision." A person might read fine print but be unable to navigate a room safely because they cannot see what is to the side. If the visual field measurement is 20 degrees or narrower, Social Security considers this blindness.

Visual field is measured using a perimeter, a machine that shows lights at different points around your field of vision and records which ones you can see. The test takes 10 to 30 minutes per eye. Your eye doctor's report must include the specific degree measurement for your better eye.

What Counts as Correction

Correction means any method that improves your vision: eyeglasses, contact lenses, intraocular lenses (implanted after cataract surgery), or refractive surgery like LASIK. Social Security requires that you have tried correction and that the measurement is still 20/200 or worse, or that your visual field is still 20 degrees or narrower.

If you have not had surgery or do not wear glasses because you cannot afford them or choose not to, Social Security will still measure your vision with correction. If you refuse to wear available correction, the agency may find you are not blind under its definition. The rule is: what is your vision when you use the correction available to you?

Some people have conditions that cannot be corrected — advanced macular degeneration, for instance, or severe scarring of the cornea. In these cases, the measurement with any attempted correction is what counts. If you have had cataract surgery and still measure 20/200 or worse, that is the measurement Social Security uses.

Medical Evidence Social Security Needs

To evaluate a blindness claim, Social Security requires a report from an eye care professional — an ophthalmologist or optometrist — that includes specific measurements. The report must state your visual acuity in each eye with correction and your visual field in each eye. A general statement like "the claimant is blind" or "vision is very poor" is not enough.

The eye doctor should use standard testing methods: a visual acuity chart for acuity measurement and a perimeter for visual field measurement. The report should include the date of the test, the specific numbers (for example, "20/200 in the right eye, 20/400 in the left eye"), and the method used. If you have had recent surgery or a change in your condition, a more recent report is better than an old one.

You can obtain this report by asking your eye doctor for a copy of your test results. If you do not have a regular eye doctor, you can see one through a community health center, a state agency for the blind, or a hospital eye clinic. Some states offer free or low-cost vision screening through their vocational rehabilitation agencies.

Blindness and Work Incentives

If you are receiving SSDI based on blindness, you have access to work incentives that other beneficiaries do not. The Plan to Achieve Self-Support (PASS) program allows you to set aside income and resources for a work goal without losing benefits. You can also continue to receive benefits while you work and earn above the usual substantial gainful activity limit, as long as you remain blind.

The Impairment Related Work Expenses (IRWE) deduction lets you subtract the cost of items or services you need because of your blindness — a guide dog, screen reader software, transportation to work, or a reader — before your earnings are counted. This can allow you to work and earn more while staying on SSDI.

Additionally, if you are blind and working, you may be able to use the Blind Work Expenses (BWE) deduction, which is similar to IRWE but has different rules. These work incentives exist because Social Security recognizes that blindness creates extra costs when you try to work.

Conditions That Often Meet the Blindness Definition

Many eye conditions can result in vision that meets Social Security's 20/200 or 20-degree standard. Diabetic retinopathy, where high blood sugar damages blood vessels in the retina, is one of the leading causes of blindness in working-age adults. Advanced glaucoma, which damages the optic nerve and narrows the visual field, often qualifies. Age-related macular degeneration affects central vision and can quickly progress to 20/200 or worse.

Retinitis pigmentosa causes progressive tunnel vision and often meets the visual field test. Cataracts that have not been surgically removed, or cataracts that remain dense even after surgery, can reduce vision to 20/200 or worse. Corneal scarring from injury or infection, retinal detachment, and severe myopia (nearsightedness) that cannot be corrected are other conditions that may meet the standard.

The underlying cause does not matter to Social Security. Whether you are blind from diabetes, injury, inherited disease, or age, the only question is whether your vision measurement meets the definition. Two people with the same eye disease might have different vision measurements and therefore different outcomes on a blindness claim.

Frequently Asked Questions

Do I have to be completely blind to may have access to under Social Security's definition?

No. Social Security's definition includes people with partial vision loss. If your vision in your better eye is 20/200 or worse with correction, or your visual field is 20 degrees or narrower, you meet the definition — even if you can still see some light, shapes, or movement.

What if my vision is 20/150 in one eye and 20/300 in the other?

Social Security measures your better eye only. In this example, your better eye is 20/150, which does not meet the 20/200 standard. You would not may have access to based on visual acuity, though you might still may have access to if your visual field is 20 degrees or narrower.

Can I be considered blind if I have not had surgery yet?

Social Security measures your vision with any correction available to you. If surgery could improve your vision and you have not had it, the agency may ask why. If you refuse available surgery without a medical reason, Social Security might find you are not blind. If surgery is not an option or would not help, your current vision measurement is what counts.

How long does it take Social Security to decide a blindness claim?

Initial decisions typically take two to three months, though this varies by state and workload. If you are denied and appeal, the process can take six months to over a year. Having complete medical records with specific vision measurements from the start speeds up the review.

If I am approved for SSDI based on blindness, can I lose my benefits if my vision improves?

Yes. Social Security can schedule a medical review at any time. If your vision improves — for example, after cataract surgery — and no longer meets the 20/200 or 20-degree standard, you could lose SSDI. You should report any change in your vision to Social Security.