Hello there, KSM1.
I'm glad to see you in the QuickBooks Community. I'd be delighted to share some information about posting a transaction for the 401 (k) contributions.
To report the contribution amount for the current year filing, you need to choose 2018 as the paycheck date of the payroll. For any transactions made in the year 2019, you may need to report them manually to the agency.
For more in-depth information about 401 (k) Plan, you visit the link below:
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