PEO vs. Payroll Service vs. Fractional HR: How to Choose

When a small business starts looking for help with HR and payroll, it runs into three options that get pitched as alternatives: a PEO, a payroll service, and fractional HR. They are not really the same kind of thing, which is why comparing them is confusing. Here is the clear version.

What each one actually is

Payroll service (Gusto, Paychex, ADP): processes pay, withholding, and tax filings. That is it. Narrow but inexpensive.

PEO (professional employer organization): becomes a co-employer of your staff and takes payroll, benefits, and certain liabilities onto its own books, usually with pooled benefits plans. Broad, with co-employment.

Fractional HR: a senior HR practitioner runs your people function on a retainer while you stay the sole employer. Broad HR expertise, no co-employment.

Three-way comparison

Factor	Payroll Service	PEO	Fractional HR
Processes payroll	Yes	Yes	Coordinates it
HR compliance	No	Yes	Yes
Employee relations	No	Limited	Yes
Benefits	Add-on	Pooled plans	Your plans/broker
Co-employment	No	Yes	No
Senior HR judgment	No	Service team	Yes, direct
Pricing	Low, per run	Per employee/mo	Flat retainer
You stay sole employer	Yes	No	Yes

The cleanest way to think about it: a payroll service runs the mechanics, a PEO takes over employment, and fractional HR gives you an expert to run the people function you keep. Match the tool to the problem you actually have.

Which one fits your situation

Choose a payroll service if

You have a small team, your HR needs are minimal, and you genuinely just need pay and taxes handled. Be honest, though: most companies past a handful of employees discover that "just payroll" leaves real compliance and people gaps.

Choose a PEO if

You want to offload employment entirely, you value pooled benefits you could not buy alone, and you are comfortable with co-employment and the eventual migration if you leave. (Full detail in fractional HR vs PEO.)

Choose fractional HR if

You want senior HR expertise and to keep control of your people, you have decent benefits or a broker, and you want flat, predictable cost. This is the common fit for 10 to 75 employee companies. (See what is fractional HR.)

They are not always either/or

A common and effective setup: a payroll service for the mechanics, plus fractional HR for the judgment, with the fractional partner working through the payroll platform. You get clean payroll and senior oversight without a PEO's co-employment. The mistake is assuming a payroll service alone covers HR; it does not, and the gap is where the risk lives.

The bottom line

Payroll services run pay, PEOs take over employment, fractional HR runs the HR you keep. Pick by the problem: just payroll, full offload, or expert support with control. For most small and mid-size businesses that want the last one, fractional HR fits, and Bevel HR provides it from $1,800/month.

Frequently asked

What is the difference between a PEO, a payroll service, and fractional HR?

A payroll service processes pay and taxes only. A PEO becomes a co-employer and handles payroll, benefits, and some liability under its own systems. Fractional HR provides a senior HR expert who runs your people function while you stay the sole employer. They range from narrowest (payroll) to fullest with co-employment (PEO), with fractional offering full HR without co-employment.

Which is cheapest?

Payroll services are cheapest but cover the least. Fractional HR is a flat retainer from about $1,800/month. PEOs charge per employee per month and scale with headcount. For a small team, payroll-only is the lowest sticker price, but it leaves compliance and HR judgment entirely on you.

Do I need a PEO or just a payroll service?

If you only need pay processed, a payroll service is enough. If you need compliance, benefits, employee relations, and HR judgment, you need more than payroll, either a PEO (if you want to offload employment) or fractional HR (if you want to keep control).

Can I use a payroll service and fractional HR together?

Yes, and many companies do. Fractional HR often works through your existing payroll software (Gusto, Rippling), adding the senior judgment and compliance oversight the software does not provide. The two are complementary, not competing.

Which is best for a growing tech startup?

Usually fractional HR, because startups want to keep control of their people and equity structure, hire across state lines, and need senior judgment without a full-time hire. A PEO can make sense if pooled benefits are a priority; a payroll service alone is rarely enough past a handful of employees.