If you attempt to input a Catch-Up 401K contribution in QuickBooks Online (QBO) Payroll, I would be pleased to provide the necessary information to address your issue.

401k catch-up is still supported by QBO. As you mentioned you run the same one-time catch-up last year, and if you want to put an entire paycheck into a 401k catch-up retirement plan this year, make sure to follow the steps. Here's how:

1. To the employee's profile, Add an Other Earnings pay type. And rename it as Taxable offset. Or create your name.
2. Then set the deduction amount to zero to Set up a retirement plan deductions.
3. To determine the gross pay amount use the Gross up formula.

For more details on zero net paycheck in QuickBooks Online Payroll, check this article: Create a zero net paycheck.

If you've already done this, I suggest contacting our Support Team to get help with QuickBooks products and services.

Here's how:

1. Open QuickBooks. Then navigate to Help, then select QuickBooks Online Payroll/Contact Us.
2. Click Contact Us, after giving a brief description of your issue, then select Continue.
3. Sign in to your Intuit account select Continue and then Continue with my account.
4. Select Chat with us or Have us call you.

Our support services are available Monday through Friday, 6 AM to 6 PM Pacific Time.

Furthermore, I am providing these resources to assist you in managing your retirement plans. They will offer you additional information on how to navigate deductions and contributions:

• Retirement plan deductions/contributions
• Retirement Topics - Contributions
• Account management gathers topics for your Intuit Account

Please update me on the results of the call or if you face any further issues or concerns. I am dedicated to meeting all your needs and am here to help. Have a great day.

after following your instructions and looking up the subject I followed the instructions right up until step 9 and then the error message came back. At this point QB will not let you go forward. I'm not sure if it's me or QB? But I'm still not able to run my catch-up 401k contributions for 2024. 

We appreciate your patience in following the steps provided by my colleague above, Whiz65. I'm here to guide you further and connect you with the team that can help resolve your payroll concern.

Since the issue persists, I recommend contacting our support team for further assistance. They have the tools and expertise to securely access your account, identify the cause of the issue, and provide a targeted resolution.

Here's how to reach a live representative:

1. Log in to your QuickBooks Online Company.
2. Click the Help button at the top of the page.
3. Choose the Search tab. Type in your concern and click enter on your keyboard.
4. Click Contact us.
5. Under Callback, click the Have us call you button. This will route you to enter your details.
6. After that, select Get a call.

Additionally, you can run payroll reports to obtain a comprehensive overview of your employees' information and payroll activities.

Please feel free to reach out if you have any other concerns about payroll in QuickBooks, Whiz65. We’re here to assist you in any way we can.