Review ownership, family attribution and service relationships before designing a plan. See how an incomplete employee census can understate employer costs.

October 13, 2025 · Financial Forte Staff

Historical article: prepared retrospectively using information available as of October 13, 2025.

Separate companies often have separate bank accounts, payroll systems and tax identification numbers. It is understandable that an owner might expect their retirement plans to be separate as well. Federal retirement-plan rules can reach a different result when ownership, family attribution or service relationships connect the businesses.

Before designing a benefit for one entity, have the administrator or qualified benefits counsel review the full ownership and services structure. Separate EINs do not, by themselves, establish separate treatment. An incomplete employer group can lead to a plan design that looks affordable or compliant only because relevant employees were left out.[1]

Start with the businesses behind the payroll

Controlled-group rules can require employees of related corporations to be treated as employed by one employer for specified retirement-plan purposes. Related trades or businesses under common control can also be affected even when they are not all corporations. The rules involve more than the name on a paycheck.[1]

Affiliated-service-group rules address certain service and management relationships. They can create aggregation issues that are not resolved by checking a single ownership percentage. The nature of the services, the parties receiving them and the ownership of relevant entities can matter.[1]

That does not mean every business sharing a vendor, office or family relationship must combine its plans. It means those facts need to be evaluated under the applicable tests. Avoid using a simplified percentage chart as a final legal conclusion, particularly where ownership passes through other entities or family attribution is involved.

Prepare an ownership chart showing each person and entity, direct and indirect interests, relevant family relationships, and changes during the year. Add a short description of which business performs services for which other business, including management arrangements and the dates those relationships began. An organizational chart designed for marketing rarely contains enough detail for this review.

See how an incomplete census changes the budget

Consider a hypothetical owner who owns 100% of two businesses. Company A employs six eligible people with total eligible compensation of $500,000. Company B employs four eligible people with total eligible compensation of $250,000. Assume the administrator confirms that the businesses must be aggregated for the retirement-plan purposes being evaluated.

The owner initially asks for a uniform 5% employer contribution based only on Company A. That preliminary estimate is $25,000. If the intended design instead provides 5% to all ten eligible employees across the confirmed group, the compensation base is $750,000 and the contribution is $37,500: $750,000 multiplied by 5%.

The difference is $12,500 before administration and other expenses. That extra amount is not a penalty for owning two businesses. It is the cost of the stated uniform contribution when the complete workforce is included. The original quote omitted relevant compensation.

Aggregation does not necessarily require every employee to receive an identical percentage or every entity to use one document. Coverage, nondiscrimination, contribution limits and the available design choices require separate analysis. The uniform 5% assumption simply makes the budget effect visible.[1][2]

If the owner had promised the original design before that review, the company might face an awkward choice between a larger budget and an employee communication that needs correction. Establish the employer group before treating a contribution illustration as an approved offer.

Revisit ownership and services when the business changes

A purchase, sale, new subsidiary or change in family ownership can alter the analysis. So can moving employees into a management company while they continue serving related operating businesses. A new payroll system is not proof that the underlying employer relationship has changed for plan purposes.

Give the administrator transaction dates and documents rather than only the year-end ownership snapshot. Employees' service histories, transfers between entities and compensation records may be needed. A change during the year can raise transition issues that should be reviewed under the applicable rules rather than assumed away.

Family attribution deserves particular care. The law contains specific attribution rules and exceptions, including changes that took effect in 2024. Neither “spouses always count as one owner” nor “separate ownership always keeps the businesses separate” is a safe universal statement.[1]

The business should also identify all existing retirement arrangements, including plans maintained by entities outside the initial proposal. Contribution limits and testing may depend on the group and the employee's participation elsewhere. An owner-only plan should not be treated as exempt from this review merely because the account was opened under a different EIN.

Put the conclusion into plan operations

Ask for a written explanation of the group determination, the facts relied on and which plan requirements it affects. The goal is not a long legal memo for every routine change. It is a clear record that payroll, HR and the administrator can use consistently.

For an ERISA-covered plan, accurate administration and prudent provider oversight can involve fiduciary responsibilities. Hiring an administrator is valuable, but the employer still needs to provide complete information and monitor the assigned work. A provider cannot reliably test employees or compensation it was never told about.[3]

Assign responsibility for maintaining the ownership chart and notifying the benefits team before a transaction closes or employees move between entities. Reconcile the census to all relevant payroll records, and confirm that employee transfers were not treated as entirely new service histories without review. If an omission is discovered, obtain a correction assessment promptly rather than silently changing next year's file and assuming the past is resolved.

A complete review can reduce the risk of missed employees, correction expense and disrupted benefit promises. It can also improve cost estimates before the business commits to a design. Bring the ownership chart, service relationships and full employee census to the next planning discussion; those facts are the foundation for a retirement benefit the business can administer with confidence.

Related reading

Have more questions about related employers and retirement plan administration? Email Dave at dave@financialforte.com to discuss your questions and next steps.

The contact invitation is current; it does not imply this contact path existed on the historical reference date.

Educational information, not personalized investment, tax, legal or benefits advice. Examples use hypothetical assumptions. Verify current rules and your circumstances before acting.

Sources

Related Posts

Retirement income, taxes and Medicare: connect the moving parts

November 12, 2026

Capital gains and tax-loss harvesting: what to check before selling

November 12, 2026

Roth conversions: when they may help—and what changes the answer

November 12, 2026