Pay stubs and W-2's seldom match.  That is why we tell people not to use pay stubs to prepare tax returns.  If there is something specific about your pay stub and W-2 that you do not understand you should talk to your employer.

Thank you for your answer!  I understood there could be difference but was interested in typical reasons for the difference.  For others, who might be interested,  I realized in mine that the difference could be explained by Group Term Life, which is a taxable benefit for me.  This was also reported on my pay slip, just not where my earnings are, but it is included in box 1 of my W2.