That’s because the initial application into either program is often denied. In fact, most SSD applications are denied on the first attempt, and many SSI candidates are turned away as well. Fortunately, applicants have recourse available to them to prove to the Social Security Administration that they are worthy applicants.
When an application is denied, either for SSI or SSD, applicants have the opportunity to appeal the decision. This appeals process can be a long one — some recipients report waiting many months or even several years — but help is available. Applicants have a right to seek legal assistance with the SSI or SSDI process. Social Security attorneys are often skilled at navigating the application process, and understand how to approach the appeal in a way that is most likely to prove the applicant’s case.
Although SSI and SSDI have several similarities, it is important to understand their differences. SSDI is available only to applicants who have worked a certain number of years and earned a certain number of Social Security work credits. There are no limitations on the current assets of SSDI recipients. By contrast, SSI is available only to disabled workers who have very few assets — about $2,000 for an individual, not counting the home. SSI is available to all disabled workers who meet this threshold, regardless of the number of Social Security work credits they have earned.
Source: Asbury Park Press, “Social Security: Can you appeal a denial for supplemental income?” Joanne Crane, Aug. 30, 2013