I have a question ... If paying an employee their salary check and I also add on that same check a payment towards their insurance, will the insurance payment be included in their salary on the W2 at the end of the year?

Are you using ezPaycheck 2019 now? Here are two options:

1. If the insurance payment is the reimbursement, please use the MISC check. Then it will not be reported on the W2 form.

MISC check feature
https://www.halfpricesof...zPaycheck_misc_check.asp 

2. If the insurance payment is part of the salary, you can pay it with the regular paycheck. It will be reported to the W2. If your company also deposit this payment for the insurance plan, you can add a pre-tax/after-tax deduction to withhold this amount from the gross pay depending on the insurance plan.

Sample - pre-tax deduction for insurance
https://www.halfpricesof...ce-payroll-deduction.asp 

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