Hello Kim,
Depending on the work done, the payroll allocation account can be a COGS account - for example for people that actively and permanently work on our project.
What I have seen more often is, however, that people used a P&L account that is a bit further down in the income statement; often around the payroll/wage&salaries section.
That is because the account is doing what its name says :-)
It allocates costs from the cost center or department of your employee to the project.
Usually, you will have a voucher that looks similar to:
DR: ProjectCostAccount - CostCenterFromProject
CR: PayrollallocationAccount - CostCenterFromEmployee
Most of the time the ProjectCostAccount is an account that you find in the COGS section of your income statement while the PayrollAllocationAccount is an account that is found near the wage&salaries accounts that you use.
Best regards,
Ludwig