What is the difference between expenses and payments?

A payment is a disbursement of money (usually in the form of a check or currency). ... payments to remit payroll tax withholdings will never be an expense. paymentsto reduce liabilities resulting from expenses reported in earlier accounting periods (e.g. payments to reduce interest payable, accounts payable, taxes payable ...

Expenses is only Unpaid routing office / site expense but the payment is paid agst. expenses / expenditure.

Expenses are costs that have been used up or have been incurred in the process of earning revenues and/or operating a business. 

A payment is a disbursement of money (usually in the form of a check or currency). Some payments are current period expenses (e.g. current month's rent payment) but many payments are not expenses of the current period.