October 6, 2025

401(k) Plan Fees Explained: How Costs Scale as Your Business Grows

401(k) plan fees can vary as your business grows, so understanding how costs scale is crucial for employers seeking the best value for their retirement plans.

For HR and Finance leaders, understanding 401(k) plan fees is essential to effective budgeting, compliance, and employee engagement. Recent research shows that approximately 80% of companies with 100 or more employees overpay in retirement plan administration fees, making fee vigilance a critical employer responsibility (Abernathy Daley 401(k) Consultants, 2024). As your business grows, the structure and scale of these costs can shift dramatically, impacting both your bottom line and workforce confidence.

With increased regulatory focus and new pooled solutions entering the market, now is the time to scrutinize your fee structure and make sure your plan remains competitive. If you’re evaluating your current 401(k) or exploring a new provider, Basic Capital’s modern 401(k) platform offers a transparent, scalable approach designed for growing teams.

The Total Cost Picture: Employer vs. Participant Fees

Clarity around who pays which fees is foundational for both compliance and trust. In the context of 401(k) plan fees, costs fall into two main groups: those covered by the employer and those paid by participants. Administrative fees, for recordkeeping, compliance, and education, may be paid by either party, and sometimes shared. These fees cover day-to-day plan operations, including legal, accounting, and trustee services (dol.gov).

Investment fees (like expense ratios) are typically deducted from participant accounts, while advisory or consulting fees can be structured either way. For mid-sized employers, industry analysis reveals that the majority pay higher-than-average fees, often due to legacy plan structures or lack of regular benchmarking (Abernathy Daley 401(k) Consultants, 2024).

Understanding your 401(k) fee structures, and communicating them clearly, reduces confusion, supports better plan decisions, and helps prevent hidden costs that erode participants’ long-term savings.

For more on how costs are split, see our guide to 401(k) Provider Pricing: True Costs for Employers vs Employees.

What Actually Scales (and Why Fees Change as You Grow)

The costs associated with a 401(k) plan don’t always rise in direct proportion to your headcount or assets. 401(k) cost scaling means that fees per participant or as a percentage of plan assets often decrease as your plan grows, thanks to economies of scale and negotiating leverage.

Here’s what drives these shifts:

Administrative fees may appear as flat or per-participant charges, but larger plans can often negotiate discounts or access pooled solutions.
Investment fees tend to fall as asset levels rise, since higher-balance plans qualify for lower-cost investment options. It’s also important to remember that higher fees don’t necessarily translate to better investment performance, and in fact, can reduce returns over time.
Advisory fees may be renegotiated or simplified as plan complexity increases, particularly when bundled service models are adopted.

Recent Department of Labor data shows a 135% increase in pooled employer plans (PEPs) between 2021 and 2022, reflecting a growing trend toward collective fee bargaining and cost reduction (U.S. Department of Labor, 2025 Pooled Employer Plan Bulletin).

Pooled Employer Plans (PEPs) not only offer economies of scale but can also simplify compliance for busy HR and Finance teams.

Yet, despite these opportunities, many mid-sized employers still overpay for their 401(k), highlighting the need for regular benchmarking and negotiation (Abernathy Daley 401(k) Consultants, 2024).

For more on how fees scale with company size and best practices for benchmarking, see How Much Should Employers Pay in 401(k) Fees? A Mid-Market Benchmark.

Reading Pricing Tables Without Surprises

What should employers look for when reviewing provider pricing? While many fees are clearly disclosed, hidden charges, like revenue sharing or wrap fees, can inflate total costs. According to Abernathy Daley 401(k) Consultants, these hidden arrangements are a primary reason why 80% of companies with 100+ employees are overpaying for retirement plan administration (hrdive.com, 2024).

401(k) benchmarking is a critical tool here: regularly comparing your plan’s fees to industry averages helps reveal these less obvious expenses. Plans are legally required under ERISA sections 408(b)(2) and 404(a)(5) to disclose all associated fees, making it important to review provider documentation with care.

Watch for terms like “revenue sharing,” “sub-transfer agency,” or “wrap fees” in plan documents. Fee transparency isn’t just best practice, it’s a fundamental fiduciary duty.

For a step-by-step breakdown of disclosure expectations and how to spot hidden fees, see our Practical Guide to 401(k) Fee Disclosures for Employers.

Scenario Planning: Growth Milestones That Trigger Fee Reviews

Consider a scenario: a company increases its workforce and assets, assuming their 401(k) plan design and fees are still competitive. Without a scheduled review or benchmarking, they may miss opportunities to renegotiate fees, potentially overpaying by thousands each year.

The Department of Labor’s 2025 Pooled Employer Plan Bulletin documents a surge in pooled plan adoption, highlighting that fee-conscious employers are proactively seeking cost savings through collective solutions. Leading consultants recommend benchmarking your 401(k) fees during any major business growth or organizational change.

As your business evolves, both your 401(k) provider comparison and plan design should be revisited at major growth milestones.

For more on how to set an effective review cadence, explore Mid-Market 401(k) Benchmarks (250–1,999 Employees): Fees & Participation.

Operationalizing Fee Governance: Owners, Calendar, and Communication

Effective 401(k) fiduciary responsibility requires more than annual reviews: it’s about building a process for ongoing oversight. Start by assigning clear ownership of fee reviews, scheduling them at least yearly, and documenting every finding and negotiation.

The Department of Labor and leading consultants recommend that employers regularly review fees and maintain a transparent record for compliance. Neglecting these steps can result in compliance risk and unexpected financial liability.

Steps for governance:

Assign a fee review owner (HR/Finance lead).
Schedule annual benchmarking against industry standards.
Document all fee changes and communications.
Educate plan participants on costs and their impact.

Regular, documented benchmarking not only fulfills your fiduciary duties but also strengthens trust with employees.

For more on structuring fee governance, see How Mid-Market Employers Evaluate 401(k) Plan Providers.

Conclusion: Why Proactive Fee Management Pays Off

The bottom line: diligent oversight of 401(k) plan fees is not just a regulatory requirement, but a competitive advantage as your business grows. Industry studies confirm that most mid-sized employers could save significantly by reviewing and renegotiating plan fees, especially as assets and participation increase (Abernathy Daley 401(k) Consultants, 2024).

The surge in pooled plan adoption is a clear signal that proactive employers are taking action. By staying proactive, employers not only reduce costs, but also substantially minimize legal and compliance risks.

Proactive fee management means better outcomes for both your organization and your employees. Ready to take the next step? Get started (for employers).