One in 4 Americans will become disabled by age 67, according to the Social Security Administration. “That means you could lose your greatest asset – your ability to earn an income,” says Steve Azoury, a financial advisor and owner of Azoury Financial in Troy, Michigan. Social Security disability insurance is designed to replace some of this lost income if you have a medical condition and can no longer work.

To receive SSDI, you will need to meet certain criteria. The exact benefits you receive will depend on your age and how much you earned during your working years. The average Social Security disability benefit amount was $1,278 per month in January 2021, according to Social Security Administration data.

Social Security disability insurance:

Those who are employed pay for the disability insurance program through taxes. Social Security collects 6.2% of worker earnings, up to $142,800 in 2021. Employers also pay 6.2% of employee wages into Social Security. The Federal Insurance Contributions Act is the law that oversees these taxes.

During your working years, you’ll pay taxes that are used to fund the Social Security disability program. If you become disabled and are unable to work, you can apply for benefit payments.

“Generally speaking, you have to have paid into Social Security through FICA taxes for five of the 10 years immediately prior to becoming disabled in order to be eligible,” says Michael Liner, founder of Liner Legal in Cleveland.

Before filling out an application, you’ll need to determine what you are now unable to do as a result of your disability. “You have to prove you are not able to do any kind of work,” says Jerry Zivic, a retired Social Security disability lawyer. “It is not whether somebody will hire you or not.”

If you can perform work, even if it isn’t related to your previous profession, you may not be eligible. For example, a surgeon might suffer a hand injury and no longer be able to carry out duties in the medical field. But if the injury isn’t severe, and the person can do other tasks such as answer the phone or walk dogs, Social Security disability benefits might not be an option.

Print out a list of the medications you take, along with their side effects, to send in with your application. You can also have your doctor list information about your condition.

“It would be helpful if your medical provider can provide a statement that you are not able to do any type of work,” Zivic says. Put your medical records together, including doctor visits, diagnoses and any other information that helps explain your disability.

The long-term outlook for your health condition will also be considered when evaluating your application. “You must be completely unable to work with a condition that is expected to last for at least a year or result in death,” Azoury says. “There are no partial or short-term disability benefits from Social Security.” If you need back surgery and are unable to work for several months but are expected to heal completely, you may not be eligible for disability benefits.

Once you have the information you need, you can send in an application to the Social Security Administration online. You can also call 1-800-772-1213 to apply. If you are deaf or hard of hearing, the number is 1-800-325-0778. Applications are also available at your local Social Security office. To apply in person, you should call and make an appointment.

If you apply at a local Social Security office, the person who interviews you will make “field office observations” about your case and take note of aspects of your behavior, appearance, grooming or degree of limitations as perceived by the interviewer.

“They note if the applicant came with a cane or a walker, or appears to have difficulty sitting for the duration of the interview,” Liner says. “It is one more opportunity to present helpful limitations to SSA that may be missed if you merely apply online or do an application over the phone.”

After you apply, the SSA will review your application, which can take several months. You will then be notified if you are eligible for benefits.

“Once eligible, benefits are set to replace about 40% of the average worker’s income,” Azoury says.

If your application is denied and you remain unable to work, you may decide to have a lawyer help oversee your case. Before hiring anyone, check that the person is an attorney.

“A lot of people that help are not attorneys and they cannot take your case to federal court if you lose,” Zivic says. In addition, attorneys are only allowed to be paid if they win the case. “The fee must be approved by the SSA,” Zivic says.

After you start receiving benefits, your file will be periodically reviewed to determine if you are still eligible. For this reason, it’s important to continue to save all medical records and information about your condition. You may need to provide documentation of your disability in the future when your case is evaluated.