If the employee is paying (reimbursing) the company immediately, you can record the entire phone bill with a debit of $100 to the company's account Telephone Expense. You will also credit Telephone Expense for $20 when you record the $20 receipt from the employee.
If the employee is not paying the company immediately, you can record the $100 phone bill by debiting Telephone Expense for $80 and debiting the asset account Receivable from Employees for $20. When you receive the $20 from the employee, you will credit the account Receivable from Employees.
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