I can share some information on how to post the 401k employer contribution, @Cheese Girl.

You can post the 401k contribution without QuickBooks Payroll by using a Journal entry. This way, you can track the payments for the employer contribution.

Here's how:

1. Select the + New icon on the Toolbar.
2. Under Other, select Journal Entry.
3. Enter the transaction date in the Journal date field.
4. On the first distribution line, in the Accounts field, enter any account listed in the Chart of Accounts. Note: If you are not sure which account receives the debit and the credit side of a transaction, consult your accounting professional for guidance.
5. Enter the transaction amount in the Debits or Credits column. Tip: The first line is typically a Debit. Once you save the transaction, you can find it in the Recent Transactions report to see whether the Debit entry had the desired effect.
6. Specify a customer, vendor/vendor, or employee associated with the line, if any, in the Name field. Note: QuickBooks Online Plus users – When the Classes and Locations feature is turned on, additional fields for Location and Class appear.
7. Continue to enter distribution lines until the sum of the Debit column entries equals the sum of the Credit column entries. Note: QuickBooks Online Plus users – When the Classes and Locations feature is turned on, additional fields for Location and Class appear.
8. Select Save.

Upon sharing the steps above, I'd still suggest consulting your accountant. They can help and guide you on which account to debit and credit to ensure your accounts are accurate.

For more details about the steps above, click this article: Record payroll transactions manually.

I'm also adding this link that you can read to learn more about 401k and how to efficiently run your payroll: 

• 401(k) Plan Overview
• Create and run your payroll

Keep me in the loop by leaving a reply below if you need more help about 401k or with your payroll. I'll be here ready to assist you. Stay safe, @Cheese Girl.