Start with the actual employers
An owner who runs two corporations may ask one payroll provider to combine both salaries under a single annual Social Security ceiling. Using one provider is an administrative choice. A common-paymaster arrangement is a specific federal employment-tax rule. Begin with the services performed for each corporation, the dates of employment, and the relationship between the corporations. A holding-company chart alone does not explain whether the owner actually works for both employers at the same time.
Publication 15-A describes common-paymaster treatment for concurrently employed individuals paid through one of two or more related corporations. Each corporation remains responsible for its own wage and tax share. The operational decision is whether the facts support that arrangement before the payroll system combines wages; it is not whether combining wages produces a desirable result.
Calculate the allocation before sending cash
Assume two qualifying related corporations concurrently employ a founder, and a valid common paymaster pays $240,000 of total annual compensation. Internal records assign $150,000 to Company A and $90,000 to Company B. Their wage-cost percentages are 62.5% and 37.5%. If a particular shared employer payroll-tax charge is $8,000 and the agreed allocation appropriately follows those wages, the intercompany charges are $5,000 and $3,000. The allocation is a hypothetical accounting example, not a substitute for the actual wage-base calculation.
Now suppose Company B reimburses only its $90,000 salary share and leaves all associated employer taxes at Company A. The group’s consolidated cash position may look unchanged, but the separate companies’ expenses and receivables become inaccurate. Build the reimbursement schedule before funding payroll. Include wage costs, employer taxes, employee deductions held for remittance and payment dates, so a single cash account does not erase each corporation’s obligations.
Document concurrency and eligibility
Prepare a dated employment record for each corporation. Identify duties, authority, expected hours, compensation and the person approving the services. Show periods in which both employment relationships exist. If the owner leaves one corporation and joins the other later, do not quietly treat the arrangement as concurrent because both corporations share investors. A change in employment timing deserves a fresh review rather than an automatic carryforward of the previous payroll setting.
Document why the corporations meet the related-corporation requirements under the governing regulation, including the applicable ownership or other relationship test. Keep the analysis separate from retirement-plan controlled-group testing, income-tax consolidation and state unemployment reporting. Similar terminology does not make those systems interchangeable. Ask the payroll provider which federal taxes the common-paymaster feature combines and which state taxes remain employer specific. Obtain a written explanation of how it assigns the wage statement and employment-tax returns.
Settle the intercompany ledger regularly
The common paymaster should produce a payroll-cost statement for each corporation every pay period or month. Reconcile those statements to each corporation’s wage expense, tax expense, bank transfers and intercompany balance. A large receivable that remains unpaid for a year can conceal an operating subsidy. It also makes it difficult to show which company ultimately bore the compensation cost. Set a normal settlement date and identify who will follow up when reimbursement does not arrive.
Use consistent employee identifiers across the payroll and intercompany records. If a bonus is earned entirely from work for one corporation, allocate it according to those facts rather than the routine salary ratio. Record the approval with the bonus calculation. The owner’s personal net pay should not be split again after payroll merely to make each company’s bank activity look symmetrical; the separate company cost ledger supplies that explanation.
Reassess when the structure changes
Review the arrangement when a corporation is sold, ownership percentages change, the owner stops serving one employer, or a new legal entity begins paying compensation. Preserve the effective-date payroll register so that wages before and after the change can be explained. If the eligibility review fails, calculate the consequences under the proper separate-employer rules instead of forcing the desired ceiling into payroll. A personal excess-Social-Security credit and an employer common-paymaster arrangement address different questions.
The completed file should contain the relationship analysis, concurrent employment evidence, paymaster designation, allocation method, reimbursement history and year-end reporting reconciliation. This article does not determine eligibility for a particular corporate group or extend the rule to every LLC, partnership or disregarded entity. Federal common-paymaster treatment also does not itself settle state employment taxes, retirement limits, reasonable compensation or related-party service pricing. Keep those reviews on their own facts and authorities.
Sources & further reading
Consult the original guidance and its effective dates. These references support the educational discussion; their application depends on the specific facts.