The U.S. Department of Labor advises people to file for unemployment benefits as soon as they lose their jobs. One reason is that it takes a few weeks to process a new claim. Another is that you're only eligible if you've worked for wages in the recent past. If you lost your job four years ago, did not file at that time and haven't been working since, it's unlikely that you will be able to receive benefits now.
Every state draws up its own rules as to who is eligible for unemployment benefits, so the specific criteria vary from one state to the next. Generally, though, to receive benefits, you must be unemployed "through no fault of your own," as the Labor Department puts it. You also must be able and willing to work. And you must have worked for wages during a recent time frame, called your "base period."
Base periods are calculated using the idea of "calendar quarters." These are three-month segments of the year: January to March, April to June, July to September and October to December. According to the National Conference of State Legislatures, nearly every state uses the same base period: the first four of the last five completed quarters before the date you file a claim for benefits. That's a mouthful, but in practice, it's not too complicated. Say you applied for jobless benefits on August 20, 2015. The most recently completed calendar quarter would be April-to-June 2015. Your base period would then be the four quarters before that one, or the 12-month period running from April 2014 to March 2015. In no state does the standard base period go back four years. So if you haven't earned wages in four years, you're not going to be eligible.
Alternative Base Periods
You must have earned a specific amount of money within your base period to qualify for benefits. Workers whose base-period earnings aren't high enough to qualify may be able to substitute an alternative base period. About one-third of states offer an alternative base period, usually the last four completed quarters. The alternative period is always closer to the date you file your claim, not farther in the past, so a claim based on a job loss four years ago won't qualify for the alternative base period either.
Extended Base Period
There is one circumstance in which wages from several years in the past could be considered. A little less than half the states offer an "extended base period" for people who suffered an illness or injury that kept them from working. They can file for benefits based on their wages before they suffered the injury or illness. However, state laws vary in how far back an extended base period can go; in many cases, even the extended period won't go back four years.