the match is not reported on page 1 of form 1065 neither guaranteed payments (those would be income on partner's return) nor line 18 - retirement plan contributions
Do not deduct payments for partners to retirement or deferred compensation plans including IRAs, qualified plans, and simplified employee pension (SEP) and SIMPLE IRA plans on this line. These amounts are reported in box 13 of K-1, using code R, and are deducted by the partners on their own returns.
to balance the return assuming they're recorded as a book expense the amount would be reported on M-1 line 4
if the LLC is taxed as an S-Corp there are no partners only shareholders for tax purposes. shareholders who perform services for the LLC are also its employees. an owner who performs no services is merely an owner and not an employee. income is allocated in proportion to ownership %. there are no guarantee payments.
That doesn't mean a formula or other means can't be used to determine their salary but no deductible salary can be paid to an owner who does not perform services.
if any of these owners did not perform services for the LLC no retirement plan contribution (either by the owner or matching contribution by the LLC) can be made for them. if such was done run to a tax pro because such an action can disqualify the plan. there are severe adverse consequences to the participants if a plan is disqualified.
matching contributions are deductible page 1 line 17 of the 1120S and are not reported by the employee.
employee contributions reduce box 1 of W-2 and are reported using box 12 of the W-2. since taxable wages have been reduced, the employee gets no deduction further deduction on their 1040
