How to enter a one time 401k employer contribution to fix a missed payment from last year

Thanks for the information, @SarahCO. Since this impacts last year’s wages and tax reporting, a payroll correction is needed. Please contact our Live Support team to handle this securely, as we can't process these sensitive updates here in the Community forum. Here's how:
 

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Once resolved, you can find the updated transaction under the employee’s Paycheck List tab reflecting their corrected 401(k) contribution.

Feel free to respond if you have any questions or additional concerns. I'm always here to help!