There really isn’t a perfect number of references to check because the number of references checked depends on the importance of the position to be filled. For key positions at the top of the organization chart, we have been asked to check as many as twelve references. For most management positions and downward, however, we recommend checking a minimum of three references.
Seldom do we check the names of references initially supplied by the candidate. We typically ask the candidate to provide the name of someone the candidate worked for directly within the last five to seven years; someone the candidate worked with on a daily basis during the same time frame; and, if possible, the name of someone who worked for the candidate. In other words, we’re asking the candidate to provide the types of references we want, not the references the candidate wants to provide.
Furthermore, we want to hear about the candidate from different points of view, ideally from above, laterally, and from below. How the candidate is viewed by a superior may be entirely different from how he is viewed by a reference who reported to him.
We’re also interested in hearing how a candidate performed over time. A possible weakness five or six years ago may well have turned into a strength during the last year or so.
So, checking three references, by our reckoning, is the ideal number for most candidates. Anything fewer than three references normally won’t provide enough job performance information upon which to base a good hiring decision.