qbteachmt
Level 15

"When I enter the elective deferral in the Kehogh/SEP/Simples Contribution Worksheet"

Which is not the type of plan her "employer" set up and maintains, because you told us it is a type of 401(k).

"I'm not even sure that the way she did this (writing a check) is allowed."

It seems they confused the concept for the employer contributing the amount deferred by the employee, and the concept of self-employed contributing.

"if it is a solo 401K should be an expense on the 1120S side."

And it's still part of Expenses to the 1120S for 401(k), because the employer contributes by holding back part of the employee's Gross Wages. In other words, the amount is already part of payroll, and the employee didn't get to take it home. That's also why they don't write a personal check to the plan administration/retirement account management firm.

The plan type matters.

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