If you are talking about - for example - a biweekly payroll from Sun Oct 5-St Oct18/14 to be paid on Fri Oct24/14 then that is very common. No need to have to track it since you should have timesheets to attach the paystubs to. Employees always fill out timesheet everyday if  not weekly so you still have a record of the unpaid hours. It is at year-end that you will need to track the unpaid wages up to the last day of the fiscal year and record that thru a journal entry as debit to wage expense and credit to wage payable. Then this JE will get reverse in the new fiscal year using the date the first paychq was generated in the new year.

In most jurisdictions it is not legal to hold back employee wages.  In Ontario, for standard employment conditions, you must establish regular paydays and pay all wages owing on that date.  A normal delay in paying wages might arise from the time it takes at the end of a pay period to actually calculate and process the cheques.  In the old days, that could take a week.  With our modern technology it usually doesn't take that long.  Postponing payment beyond a week after the end of the pay period should not be necessary.

TedR - it is indeed quite legal to holdback wages for a reasonable and consistent period of time. It could be a day or a month. Every company and payroll situation is different. Typically in labour, a week is held back. Whether "necessary" or not, this is certainly reasonable and legal. In many situations it takes several days to accumulate, record, process, verify and analyze a payroll run so at least a week is needed despite the fact that we have moved to computers.

P. Brulotte -- as Smithco posted - there is nothing to track in your payroll module. If you want to record the accrual for unpaid wages at the end of every accounting reporting period, that would be a manual general journal entry to adjust the liability and expense accounts, which would then be reversed the first day of the next reporting period, or just adjusted again at the end of the next.