People lose touch with friends and family for all kinds of reasons. Occasionally, the connection is so far lost that there is no way to know if the person has relocated or has died. By using some online research techniques, though, it is possible to find out if the person you're looking for is dead.
Record the person's first and last name, their last known address, a birth place, birth date, the date that you were last in contact and any other identifying information you can remember. These will be the primary clues to help you find out if the person you know has died.
Check the public record for the town or city that the person was living in. Deaths are listed in the public record for each municipality.
Using the person's last known address, search the obituaries section in all of the newspapers that deliver to that region. When a person dies, there is generally a record of it in some local news source. Search the newspaper's online obituaries, and call the editor of the obituaries to support your findings.
Check Legacy.com, a website that collects obituaries from more 700 newspapers in the United States, Europe and Australia. There is a good chance that if the person you know has died, she will be listed on Legacy's website.
Get in touch with the person's employer, especially if the person you know was employed the last time you were in contact. If your friend or loved one died while working for that company, someone in the office will know or have record of it.