Will the wages on my W-2s change?
Beginning with W-2s for 2013, slightly different pay periods will be reported than in the past due to the fact that your wages are reported based on when the funds have been made available to you. With a monthly schedule, the entire month of December is reported in the next tax year, because you always receive the funds for the entire month of December in January.
With a biweekly schedule, some of the constructive receipt of funds for December work will happen in December, and some in January. W-2s for 2012, which will be sent out in January 2013, will not be affected by the biweekly conversion, since the conversion is happening in 2013.