The best way to get the exact date of your employment is to call the human resources department of your previous employer, if the company is still in business. If not, call the Internal Revenue Service or the Social Security Administration; they keep records of your work history. Look for old tax returns or call your accountant if you used one to file your returns. You could also try applying for a credit check, as those companies sometimes provide a record of your history of employment with their reports.
Work on Your Memory
Jog your memory by trying to connect the job with other events that would have occurred at the same time. For example, if you remember that the tragedy of 9/11 occurred while you were at the job, this may remind you of the time period you worked there. Reconcile significant life cycle or family events with the job you held at the time. For example, was it when your youngest child started preschool? The year your sister got married? Perhaps you remember a major snowstorm when you starting working there and can determine the season.
Pick the Brains of Friends and Co-Workers
Call friends, family and former co-workers to help you. Perhaps a friend will recall conversations you had about your job while he held a position elsewhere. If he knows the dates he was working, it could help you get closer to the dates you are seeking. Did you get lifts to work with a neighbour? Maybe she can help pinpoint the dates she remembers driving you.
Reformat Your Resume
If all your attempts to get the exact dates of your employment fail, consider using a format for your resume that highlights skills over employment history. If you only know the months or years you worked, but not the exact start and end days of your employment, just record what you do know.