ADP TotalSource and Insperity are both large PEOs that serve companies across the US, and on paper they look much alike. Both are on the IRS list of PEOs certified to handle federal payroll taxes. Both are accredited by ESAC, a nonprofit that checks PEOs' finances. And in the public documents we found, either side can end the standard contract with 30 days' written notice. The real differences are in company size, how each delivers HR help, which health insurers stand behind the plans, and how long the larger-company contracts lock in pricing. This page sets those facts side by side from each company's own filings and documents. It does not pick a winner.

A PEO, or professional employer organization, is a company that becomes a co-employer of your staff. It runs payroll and files payroll taxes under its own tax ID, usually offers its own health plan, and splits the other employer duties with you. You still run your business and direct your people.

The short version

  • Both are large, established PEOs. ADP TotalSource reports more than 770,000 employees on its PEO. Insperity reports about 312,000. The two count on different dates, so treat the figures as rough.
  • Both pass the two outside checks open to PEOs: IRS certification and ESAC accreditation.
  • ADP says its PEO serves companies with 5 to 1,000 or more employees. Insperity says it targets companies with about 10 to 5,000.
  • Which health insurers you can offer depends on your state. Insperity names its main insurers in its annual report. ADP does not list them on its PEO page. Ask both what they offer where your staff live.
  • Neither publishes prices. Get both proposals in writing, for the same services, before you compare.

First, which ADP?

ADP sells more than one product, and many "ADP vs Insperity" pages mix them up. ADP TotalSource is ADP's PEO. ADP Workforce Now and RUN Powered by ADP are payroll and HR software, where you stay the only employer. ADP says TotalSource runs on its Workforce Now technology, so the screens may look familiar, but the legal setup is different.

Insperity is the same. Its PEO comes in three versions: HR360, HR360 Select Edition and HRScale. HRCore is its payroll and HR software, which is not a PEO. We sort out the same question for 15 brands in which payroll companies are PEOs.

The two side by side

Two terms first, in plain words. The IRS list of certified PEOs means the IRS has checked that a PEO meets its rules for paying federal payroll taxes on your staff's wages. ESAC accreditation means an independent nonprofit checks the PEO's finances and its payment of payroll taxes and insurance. Neither one is a ranking. Our guides to the IRS certified PEO list and ESAC accreditation explain both.

We checked every row below on November 2, 2026, against each company's own annual report filed with the SEC (the Securities and Exchange Commission), its own web pages or documents, the IRS list of certified PEOs and ESAC's list of accredited PEOs. Where a company does not publish a fact, the table says so rather than guessing.

ADP TotalSource vs Insperity: public facts, checked November 2, 2026
FactADP TotalSourceInsperity
On the IRS list of certified PEOs?Yes: ADP runs TotalSource through 18 separate legal companies, all certified since January 1, 2017Yes: two legal companies, Insperity PEO Services, L.P. (since January 1, 2017) and Insperity PEO HR, Inc. (since January 1, 2026)
ESAC accredited?YesYes
Where it servesAll 50 states"Throughout the United States"
Company size it says it serves5 to 1,000+ employeesTargets about 10 to 5,000 employees
Size todayMore than 19,000 client companies and 770,000 employees (June 2026)About 312,000 employees a month on average (late 2025). No client count given
Health insurersNot listed on its PEO page. One ADP contract made public in 2023 offered Aetna, and each client company picks one insurer for all its staff. In Hawaii, ADP names HMSA (Hawaii's Blue Cross Blue Shield plan) and Kaiser PermanenteUnitedHealthcare covers about 85% of people on its plans. Others named: Kaiser Permanente, Blue Shield of California, HMSA (Hawaii) and Harvard Pilgrim (New England)
Workers' comp (insurance for on-the-job injuries)ADP's own insurance company, ADP Indemnity, which buys its own coverage from ChubbChubb, since 2007
Standard contractOne-year term that renews each year. Either side can end it with 30 days' written notice (one 2023 contract)Price set for one year. Either side can end it with 30 days' written notice (most clients on HR360, its main PEO version)
Contracts for larger companiesNot publishedPrices usually set for two years for companies with about 150 to 5,000 employees. HRScale clients are expected to commit for longer

Each row comes from the sources listed below the table. ADP's contract terms come from one ADP TotalSource contract that a California public hospital district published in 2023; your contract may differ. The two companies count employees on different dates and in different ways, so the size row is a rough guide. Neither company publishes prices.

Where each row comes from:

Where each one may fit, three points each way

None of these points makes one company better. Each is a fact that matters more to some buyers than to others.

Points that may favor ADP TotalSource

  1. It says it serves very small companies. ADP says TotalSource serves companies from 5 employees. Insperity's stated target starts at about 10. If you have 5 to 9 people, that difference is worth asking both about.
  2. Same technology if you already use ADP. ADP says TotalSource runs on ADP Workforce Now. If you already use that software, ask what carries over to the PEO, such as pay history and employee records.
  3. All 50 states, in writing. ADP states that TotalSource serves all 50 states. Insperity says it serves clients "throughout the United States" without listing states. If you have staff in several states, ask Insperity to confirm each one.

Points that may favor Insperity

  1. Its main health insurers are named. Insperity's annual report names its insurers and says UnitedHealthcare covers about 85% of the people on its plans. If your employees want to keep a particular insurer or doctor network, check both companies' options for your states.
  2. HR staff in local offices. Insperity says it has HR and service staff in most of the 44 local markets where it sells, and that it offers in-person HR help there. Ask both companies how you would reach your HR contact, and whether anyone would visit.
  3. Options built for bigger companies. For companies with about 150 to 5,000 employees, Insperity offers HR360 Select Edition, which it describes as a lower-cost version that usually needs a longer commitment, and HRScale, its newest version, which became available in February 2026. Ask ADP how its contract would differ for a company your size.

What the two have in common

On several points, the two are closer than they first look.

  • Leaving. In the public documents we found, both standard contracts can be ended by either side with 30 days' written notice. Ending a PEO contract still means moving your health plan, workers' comp and payroll, so plan the exit before you sign. See PEO contract terms.
  • Prices can change. In the 2023 ADP contract, ADP could change its fees after the first year with 30 days' notice. Insperity sets standard prices for one year. Either way, expect a yearly renewal price, and ask how it will be worked out.
  • Workers' comp. Chubb is behind both programs. At Insperity, Chubb is the insurer. At ADP, Chubb insures ADP's own insurance company. See how workers' comp works with a PEO.
  • A check before you join. Insperity says it runs an "employer risk evaluation" before it makes an offer, and that its sales process typically takes about 90 days for companies under 150 employees. Ask ADP whether it runs a similar review and how long its process takes.

What the table can't tell you

Public documents cover the structure, not the experience. They don't tell you how fast each company answers the phone, how well its plans fit your employees' doctors, or what you would pay. Those answers come from the proposals and from questions you ask directly. Bring the same list to both: our questions to ask a PEO is a good start. Ask for:

  • the legal company that will be your co-employer, so you can check it on the IRS list;
  • the health insurers and plans available in each state where you have staff;
  • the full contract, including the notice period and how renewal prices are set;
  • who your HR contact will be, and how you reach them.

For each company's directory listing, see the profiles for ADP TotalSource and Insperity.

The bottom line

ADP TotalSource and Insperity are both certified, accredited and national. The useful differences are smaller and more specific: the size of company each says it serves, how each delivers HR help, which health insurers each offers in your states, and how long larger-company contracts lock in prices. Put both proposals side by side for the same services before you decide.

If you would like help comparing them, or PEOs beyond these two, request a consultation and we will connect you with our independent broker. The consultation is free to you. If you sign through the broker, he shares part of his fee with us. Expect the consultation to take several business days.

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