Running a 401(k) plan has never been simple, and the landscape continues to evolve. Between new regulations, enhanced technology, and rising expectations around fiduciary oversight, employers today interact with more service providers than ever. Understanding who these providers are and what they do is essential to keeping your plan compliant, efficient, and cost‑effective.
At the center of every 401(k) plan are three groups:
- Employees (participants)
- The employer (plan sponsor)
- Third‑party service providers
Let’s take a closer look at the key third‑party providers you’re likely to encounter.
Custodians: The Plan’s Financial Safeguard
Federal law requires that 401(k) assets be held in a qualified custodial account. The custodian is a financial institution responsible for safeguarding assets and executing trades based on instructions from the recordkeeper. In recent years, custodians have expanded their cybersecurity protocols and reporting capabilities as regulators have increased scrutiny around data protection and fraud prevention. While participants rarely interact directly with the custodian, this role is foundational to the plan’s integrity.
Recordkeepers: The System of Record
Recordkeepers maintain the official accounting of all plan assets and participant activity. With today’s plans offering Roth contributions, after‑tax contributions, automatic enrollment, automatic escalation, managed accounts, and more, accurate and real‑time recordkeeping is essential.
Modern recordkeeping platforms now integrate payroll feeds, provide mobile access, and offer more transparent fee disclosures than they did a decade ago. They also support provisions from the SECURE Act 2.0, including updated required minimum distribution rules and expanded Roth options. For example, the IRS’s 2026 cost‑of‑living adjustments outlined in IRS IR‑2025‑111 and the technical guidance in IRS Notice 2025‑67 are now automatically incorporated into most recordkeeping systems.
Third‑Party Administrators (TPAs): Compliance and Plan Operations
TPAs handle many of the day‑to‑day administrative and compliance functions on behalf of the plan sponsor. Their responsibilities typically include:
- Ensuring the plan document remains compliant with IRS and Department of Labor rules
- Performing annual nondiscrimination testing
- Preparing Form 5500 and other required filings
- Assisting with loans, distributions, and hardship withdrawals
- Supporting plan amendments and design changes
- Coordinating with payroll and recordkeeping systems
As SECURE Act 2.0 continues to roll out, TPAs have taken on an even more important role in helping employers navigate new rules around long‑term part‑time employees, catch‑up contributions, and emergency savings features. Industry updates from organizations like the International Foundation of Employee Benefit Plans help TPAs and employers stay aligned with evolving requirements.
Plan Investment Advisor: Fiduciary Guidance and Participant Support
The investment advisor helps the plan sponsor design, monitor, and improve the plan. Depending on the engagement, an advisor may:
- Assist with plan design and vendor selection
- Serve as a 3(21) co‑fiduciary or 3(38) investment managers
- Build and monitor the investment lineup
- Provide participant education and financial wellness resources
- Help the sponsor understand and meet fiduciary obligations
The advisor’s role has become increasingly important as employers face heightened expectations around fee transparency, prudent investment selection, and participant outcomes. Many employers now prefer advisors who accept fiduciary responsibility, reducing conflicts of interest and simplifying oversight.
Media coverage, including CNBC’s reporting on 2026 retirement plan changes and industry summaries like Gusto’s contribution limit guides highlight how quickly the regulatory environment shifts, underscoring the value of a knowledgeable advisor.
Why Understanding Your Providers Matters
A well‑run retirement plan requires coordination among all these parties. When roles are unclear or services overlap, plans can experience unnecessary costs, operational errors, or compliance issues.
Taking the time to understand:
- Who your providers are
- What services they deliver
- How they are compensated
- Where your fiduciary responsibilities begin and end
…is one of the most important steps toward maintaining a healthy, efficient, and participant‑focused retirement plan.
Your employees rely on this benefit for their long‑term financial security. Ensuring that your service providers are effective, transparent, and aligned with your goals is simply part of being a responsible plan sponsor.
Ready to Strengthen Your Company’s Retirement Plan?
A well‑designed 401(k) or 403(b) plan is one of the most valuable benefits you can offer your employees, but it requires the right partners to run smoothly. Armbruster Capital has extensive experience helping employers build and maintain retirement plans that are transparent, cost‑effective, and aligned with their fiduciary responsibilities. Our team provides investment oversight, plan design guidance, vendor coordination, and participant education, so you can focus on running your business while knowing your plan is in good hands.
If you’d like to review your current plan or explore how our employer retirement plan services can support your organization, contact us today. We’re here to help you create a retirement plan that truly works for your employees and your business.
Disclaimer: Armbruster Capital Management’s views as portrayed in this post are subject to change based on market conditions and other factors. These views should not be construed as a recommendation for any specific plan feature or design. Investing involves risks, and the value of an investment will fluctuate over time; one may gain or lose money as a result. Past performance is no guarantee of future results. Third-party sites and materials are available for access at your own risk.