When you write an employee a check for whatever reason, make sure to add those to payroll in order for employee wages to be filed correctly on the W2.
There may be occasions when an employer would write an employee a manual check. A manual check is a check that was issued to an employee outside of the payroll system. This could be for an error in payroll, reimbursement for a business expense or as a bonus for the employee.
No matter the reason for a manual or voided check, make sure to add this to your payroll process. If working with a payroll vendor, make sure to send those along before year end. The employee will not receive an additional check, but the wages must be reported and payroll and added to the employee's W2.
Failure to do so can result in an incorrect W2 for which an adjustment will need to be made. W2 errors can result in penalties and fines levied by the IRS.