It is a common misconception that you have to be off work for a year before you can apply for or collect Social Security disability benefits. This is not true. Therefore it is always best to apply for disability as soon as you are no longer able to work if you believe (and there is medical evidence to back up your belief) that your injury or disease will prevent you from working and your condition is expected to last at least 12 months or is expected to result in your death.
But let’s say you are disabled and unable to hold a job and you held off applying for disability benefits because you were hoping your medical condition would get better. Can you get Social Security disability benefits for those months when you were disabled but before you applied? The short answer is: yes. The Social Security Administration’s website, SSA.gov says, “We may pay Social Security disability benefits for as many as 12 months before you apply if we find you had disability during that time and you meet all of the other requirements.”
However (and here is where it gets a bit complicated) the law says that Social Security Disability Insurance (SSDI) can be paid only after you have been disabled continuously throughout a period of five full calendar months. SSDI benefits begin with the sixth full month after the date when you were unable to work due to your disability as established by the Social Security Administration. This is called the “date of entitlement”. You will not be paid any disability benefits for any month during the waiting period.