A cash balance plan is a separate defined benefit pension. Combining it with a 401(k) can create additional retirement funding opportunities, but the DC allocation cannot always be optimized in isolation.
Two plans with different funding rules
A 401(k) profit-sharing plan allocates contributions to individual accounts. A cash balance plan promises a defined benefit expressed through a hypothetical account, and an actuary determines required funding under the applicable rules.
A cash balance contribution is not simply another discretionary profit-sharing deposit. Investment performance, benefit promises, actuarial assumptions and funding requirements affect the amount and timing.
An example of the planning question
Imagine two owners who have reached their desired DC contributions but want to save more. Their first question is whether the business can support the pension commitment and the employee benefits required across the combined arrangement.
| Funding item | How to determine it |
|---|---|
| Owner 401(k) and profit sharing | DC limits, objectives and testing |
| Employee DC contributions | Allocation and combined-design requirements |
| Cash balance funding | Actuarial calculation for the adopted benefits |
| Total employer commitment | Combine actual funding needs and service costs |
If an initial DC illustration assumed $15,000 for employees and the coordinated design requires $21,000, the business needs to budget the $6,000 difference as well as pension funding. Those figures illustrate budgeting only; they are not a combined-plan gateway formula.
Why the standalone 5% shortcut may not apply
When defined benefit and defined contribution plans are combined for nondiscrimination testing, additional rules apply. The familiar standalone DC minimum gateway is not a universal answer for the combined arrangement.
Do not import a generic “cash balance plus 401(k)” contribution figure from an age chart and treat it as a quote. Actual benefits and costs depend on the full census, plan provisions, existing benefits and actuarial calculations.
Who should coordinate the work?
The DC testing provider, pension actuary, document provider and accountant should use a consistent census and clear owner objectives. Identify who owns each testing and funding calculation and who gives final contribution instructions.
This guide explains the relationship between the plans. The public NewComparability.com calculator does not perform cash balance actuarial valuations or combined DB/DC testing. Use an actuary for the pension design and funding analysis.
Explore the next step
Try the free scenario calculator with hypothetical inputs, or compare more allocation examples. The methodology guide explains what the calculator does and does not test.
Sources & further reading
- Treasury Regulation §1.401(a)(4)-9: combining plans for testing
- Treasury Regulation §1.401(a)(4)-8: cross-testing and the gateway
- Internal Revenue Code §414: related employers and special rules
Educational content updated September 18, 2026. Examples are fictional; they illustrate funding choices and do not constitute final testing or plan-specific advice.