Gusto 401(k) (2026): Guideline Integration, Costs, and Tax Credits

Gusto offers 401(k) retirement plans through its Guideline integration, and because it runs your payroll too, employee deferrals and employer matches are deducted and funded automatically every pay run. New plans may qualify for federal tax credits that offset startup costs, and Gusto supports auto-enrollment to lift participation. I added a 401(k) to my Gusto account a while back, and the reason it was painless is the same reason all Gusto benefits are painless: payroll already knows everyone’s contribution, so nothing has to be reconciled by hand.

Here’s how the integration works, what it costs, how matching and auto-enrollment function, and which tax credits apply to new plans.

How the Gusto + Guideline integration works

Gusto’s 401(k) is powered by Guideline, a dedicated 401(k) provider, connected so tightly that you administer most of it from inside Gusto. The integration means:

• Employee deferrals are deducted from each paycheck automatically
• Any employer match is calculated and funded each run
• Contribution data syncs between Gusto and Guideline without manual exports
• New hires can be enrolled as part of normal onboarding

The practical effect is that once the plan is set up, ongoing administration is close to zero. You’re not uploading contribution files or chasing mismatches between your payroll system and your 401(k) provider — they’re the same pipeline.

What it costs

A 401(k) has two cost layers: the provider’s plan fees and the participant-level investment costs. The provider fee is paid to Guideline for running the plan; your Gusto subscription is separate.

Because Gusto bundles no extra benefits-admin surcharge on top, the incremental cost of offering a 401(k) is essentially the Guideline plan fee plus whatever match you choose to fund. For how the Gusto subscription itself is priced, see the Gusto pricing guide.

Employer match and auto-enrollment

Employer match is optional and flexible. You can offer a match (a common formula is matching a percentage of employee contributions up to a cap), set a different structure, or offer no match at all and simply give employees access to a plan. Whatever you choose, Gusto calculates and funds it automatically each payroll run, so you don’t manually compute match amounts.

Auto-enrollment automatically enrolls eligible employees at a default contribution rate unless they opt out. It’s one of the most effective ways to raise participation, because inertia works in employees’ favor instead of against them. Gusto supports auto-enrollment as part of plan setup, which makes the benefit actually get used rather than ignored.

Tax credits for new plans

This is the part many small businesses miss. Under federal law (the SECURE Act provisions), new 401(k) plans can qualify for tax credits that offset startup and administrative costs for the first few years, with additional credits available for offering auto-enrollment and for employer contributions to employees’ accounts.

For a small business starting its first plan, those credits can cover a substantial share of the early costs — sometimes most of them. That changes the math on whether you can afford to offer retirement benefits at all. The exact amounts depend on your headcount and contributions, so it’s worth confirming the current figures with a tax advisor, but the headline is that the federal government actively subsidizes new small-business 401(k) plans.

Why run a 401(k) through Gusto

The case for Gusto’s 401(k) is the same case as for keeping any benefit in one platform: correctness and zero reconciliation. Every deferral and match is a payroll event, and when payroll and the 401(k) are one connected system, those events can’t drift out of sync. You also get one onboarding flow for new hires instead of two, and employees see their retirement contributions alongside their pay and other benefits. The broader stack is covered in my Gusto benefits overview, and Gusto vs. ADP compares how retirement benefits are handled across platforms.

How to get Gusto’s best deal

Gusto doesn’t use a typed coupon code. The current offer is a referral link that pays a Visa gift card after your first paid payroll — $100 for businesses with fewer than 10 employees, $200 for 10 or more — plus 3 months free on your subscription. Click the referral link before you sign up, create your account, and run one paid payroll to qualify; the gift card arrives within 30 days of your first paid invoice.

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Frequently asked questions

How does the Gusto 401(k) work?

Gusto offers 401(k) plans through its Guideline integration. Employee deferrals and any employer match are deducted and funded automatically with each payroll run, and contribution data syncs between Gusto and Guideline without manual file uploads.

How much does a Gusto 401(k) cost?

You pay Guideline’s plan administration fee (a monthly base plus a per-participant fee) and standard fund expense ratios, separate from your Gusto subscription. An employer match is optional and funded by you. New plans may qualify for federal tax credits that offset much of the early cost.

Can I offer an employer match with Gusto?

Yes, and it’s optional. You choose a match formula (or none), and Gusto calculates and funds the match automatically each payroll run. You can also offer a plan with no match so employees still get access to tax-advantaged retirement savings.

Are there tax credits for starting a Gusto 401(k)?

Yes. New 401(k) plans can qualify for federal tax credits that offset startup and administrative costs in the early years, with extra credits for auto-enrollment and employer contributions. Confirm the current amounts for your situation with a tax advisor.