Short answer: If nobody at your company does HR full time, pick a 401(k) provider that takes the 3(16) plan administrator role in writing, so notices, testing and filings are its job, and that pulls contributions from your payroll automatically. Even then, you still choose and monitor the provider and send accurate payroll data. This list compares 401GO, Basic Capital, Betterment at Work, Fidelity Advantage 401(k), Human Interest and Vestwell on those points, from each provider’s own materials as of November 2026. Worried about picking a newer firm? Read is it risky to choose a newer 401(k) provider.

Basic Capital publishes this page and is one of the providers listed. Providers appear in alphabetical order, not ranked. Each fact comes from the provider’s own website or help center, checked November 10 to 11, 2026.

What “hands-off” can and can’t mean

A 401(k) has jobs that someone must do every year: send required notices, run nondiscrimination tests, file Form 5500, process loans and distributions, and pick and monitor the funds. Two roles can move most of that to a provider:

• 3(16) plan administrator: runs plan operations (notices, testing, filings).

• 3(38) investment fiduciary: selects and monitors the fund menu.

What can’t move: the Department of Labor says that even when employers hire service providers, “there are still certain functions that can make an employer a fiduciary,” including choosing and monitoring those providers (DOL, Meeting Your Fiduciary Responsibilities). You also own the accuracy of the pay and hours data you send. A pooled employer plan moves more of the sponsor role to a pooled plan provider, if you are willing to give up some plan design control (see pooled plans).

How we compared providers

1. 3(16) in writing: does the provider itself take the plan administrator role, and on which plans or tiers?

2. 3(38): is an investment fiduciary built in, optional, or brought by an adviser?

3. Payroll: do contributions sync from payroll, or does someone upload files?

4. Support: can the person who runs payroll get a fast answer?

At a glance

The providers

401GO

• Says it “is the TPA, recordkeeper, custodian (through our partner Matrix Trust), and 3(38) investment fiduciary all in one”; its pricing page lists 3(16) plan administration and a 3(38) fiduciary. (401GO pricing page, retrieved 2026-11-11)

• Ask: which payroll systems sync directly through an API, and how your payroll is handled if it does not.

Basic Capital

• Basic Capital Recordkeeping Services serves as 3(16) plan administrator for the administrative functions in its service agreement, and Basic Capital handles admin, compliance testing and Form 5500 filing.

• Optional 3(38) through Basic Capital Advisors LLC, a New York state-registered investment adviser, under a separate agreement.

• 300+ payroll integrations. Active Compliance monitors ADP, ACP and top-heavy tests continuously, flags employees enrolled at 0% and drafts outreach for the admin to send. See Active Compliance.

• Every plan gets a dedicated manager; 25-minute average response time, and 80% of issues resolved within 24 hours.

• Ask: what data you are still responsible for sending, and how payroll errors are flagged.

Betterment at Work

• As “limited 3(16) plan administrator,” Betterment handles “annual compliance testing (ADP/ACP, top-heavy), calculating contributions, preparing signature-ready Form 5500s,” and offers “a turnkey 3(38) fund lineup.” (Betterment help center, retrieved 2026-11-11)

• Its pricing page lists 3(38) and 3(16) fiduciary services. (Betterment at Work pricing page, retrieved 2026-11-11)

• Ask: what “limited” leaves with you.

Fidelity Advantage 401(k)

• Fidelity “performs most administrative duties as the Plan Sponsor, 3(16) and 3(38) fiduciary, which relieves the employer of significant fiduciary risk and administrative burden.” (Fidelity small business 401(k) page, retrieved 2026-11-11)

• Ask: how much plan design you can change, since Fidelity is the plan sponsor.

Human Interest

• “Human Interest’s 3(16) Fiduciary Services are included in Human Interest’s Complete and Concierge 401(k) plans,” and it offers “select 3(38) and 3(21) services.” (Human Interest financial advisors page, retrieved 2026-11-11)

• Ask: which tier you are quoted on, since 3(16) is tier-dependent.

Vestwell

• Vestwell says employers “can get reliable recordkeeping, reporting, plan tracking, government form filing, 3(16) fiduciary services, and compliance support all in one place.” (Vestwell retirement plans page, retrieved 2026-11-11)

• Ask: which of those services are included on the tier you are quoted.

Before you sign: five questions for a team with no HR

1. Which fiduciary roles do you take, and which section of the service agreement says so?

2. Who sends each required notice, and who signs Form 5500?

3. How do contributions reach the plan from our payroll, and who catches a missed deduction?

4. If a test fails, who calculates the fix and who approves it?

5. Who do we call, and how fast do you answer?

Our guide to 401(k) features for lean HR teams covers the features that save the most time, and 3(16), 3(21) and 3(38) explained covers the roles. If you lead people operations on your own, see Basic Capital for people leaders, or book a demo.

References

Competitor sources are listed as plain text.

• U.S. Department of Labor, EBSA. (2021, September). Meeting your fiduciary responsibilities. https://www.dol.gov/sites/dolgov/files/ebsa/about-ebsa/our-activities/resource-center/publications/meeting-your-fiduciary-responsibilities.pdf

• 401GO. (n.d.). Pricing. Retrieved 2026-11-11.

• Betterment. (n.d.). What fiduciary roles does Betterment play? Retrieved 2026-11-11.

• Betterment. (n.d.). Betterment at Work pricing. Retrieved 2026-11-11.

• Fidelity Investments. (n.d.). Small business 401(k). Retrieved 2026-11-11.

• Human Interest. (n.d.). Financial advisors. Retrieved 2026-11-11.

• Vestwell. (n.d.). Retirement plans. Retrieved 2026-11-11.