Payroll is a major expense for most companies, one that often needs its own department -- human resources -- to address personnel issues and write paychecks. Payroll is also a deductible business expense and, like most other deductible expenses, it accrues and builds up balances before the checks have to be written. Payroll expenses are managed by both HR and accounts payable, depending on where they fall in their payment cycles and whether they raise more complex issues than simply accruing and paying monetary balances.

Human Resources and Payroll

A human resources department is responsible for managing most aspects of a company's relationship with its employees, from hiring and firing to benefit structures. Human resources manages payroll by calculating paycheck amounts, writing paychecks and managing employee benefit accounts. Payroll falls under human resources in the sense that the department takes care of the ongoing tasks associated with paying employees. Companies also sometimes maintain separate bank accounts dedicated to writing employee paychecks, and these accounts are managed by their human resources departments.

Accounts Payable and Payroll

Accounts payable is a category for organizing business financial information that includes all transactions that have accrued but have not yet been paid. Because you do not pay employees for their work every single day, payroll balances accrue between pay periods. Whether a business actually lists these amounts with its payable balances, interim payroll is an outstanding financial liability that must eventually be paid. Any honest accounting of payable amounts should include accrued payroll along with unpaid balances from suppliers.

Tax Accruals

Human resources withholds tax amounts from paychecks, and these sums accrue to various tax agencies throughout each tax period. Withheld taxes are payable liabilities and can therefore be categorized under accounts payable. In addition to the sums that are withheld from employee paychecks and paid periodically, accrued tax liabilities include matching employer contributions for Social Security and Medicare as well as sums that must be paid quarterly to state unemployment and industrial insurance agencies.

Benefits Payments

When human resources withholds amounts from employee paychecks for employee contributions for benefit programs such as health insurance and retirement account contributions, these amounts may not be paid immediately to the agency or institution that processes them. For example, if you make health insurance payments monthly but spread out employee contributions over the course of the month, the amounts that have been withheld but have not yet been paid are financial liabilities that can be classified as accounts payable.