If you are referring to a US payroll, the liability for payroll withholdings and employer payroll taxes is created when the payroll check is issued, and therefore the Check Date is the most accurate date to use as the Accounting Date. The General Ledger tax liability accounts will correctly reflect the date the liability accrues when the check date is used as the accounting date.

Job Cost transactions created from Payroll processing record both a Transaction Date and an Accounting Date.  For payroll time entries sent to Job Cost, the Period End date will be recorded as the Transaction Date and the Check Date will be recorded as the Accounting Date.

For specific reporting needs from Job Cost, reports can be modified to use either the Transaction Date or the Accounting Date when filtering by a range of dates.

The Payroll module also provides a Task item to Accrue Payroll which allows Time Entries that are not yet issued as checks to be Accrued to Job Cost and General Ledger.

I agree with Art.  For US payroll, we use the check date as the accounting date.  No issues with taxes or with JC.  Can't answer for Project Management as we don't have it.  

"The Payroll module also provides a Task item to Accrue Payroll which allows Time Entries that are not yet issued as checks to be Accrued to Job Cost and General Ledger."

Can you expand on this function a bit?

I am currently using Sage 100, but am considering upgrading to Sage 300.  One of my frustrations with Sage 100 is job costing the payroll.  If I have employees working the last week of a month, the payroll ends up posting to the following month.  But if we bill the project on the final day of the month, and run a job profitability report for the month, I might have all the income in month N, but all the labor costs month N+1.

Does this task item in Sage 300 allow me to accrue the costs by job and post an "accrued payroll cost" to each job?

Good Afternoon!

Sage 300 CRE does allow you to accrue your payroll time entries to Job Cost and General Ledger.  Only Pays are accrued.  You do have choices on dates, you can choose Period End Date or Accounting date to accrue your time entries.  If you choose Accounting date, you can specify which entries will accrue by using a conditon on date.  Your Burden items will flow to JC and GL when you post the checks.

We do have a knowledgebase article which explains how you can do this in detail #26554.

I hope this helps!

Gaylene