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LeadChange Group

ASO Services

ASO Services Comparison

How to compare administrative services organization products: the capabilities we check against each vendor’s own documentation, and the products verified so far.

By LeadChange Research TeamUpdated

LeadChange may earn a fee when you request pricing through our site or follow a sponsored link. Rankings never depend on whether a vendor pays us.We may earn a fee.

What we compare

Verified so far: ADP Comprehensive Services, C2 Essentials ASO, Connor & Gallagher OneSource ASO, Easeworks ASO, XcelHR ASO, AsureWorks, guHRoo ASO, and VertiSource HR ASO. Their published facts do not yet cover the same capabilities, so a side-by-side table would be mostly empty; these are the capabilities each one is checked against.

Capabilities in the comparison

  • No co-employment

    The client stays the only employer: the provider does not co-employ staff or share employer liability.

  • Payroll and tax filing

    Runs payroll and files and deposits payroll taxes under the client's own EIN and state accounts.

  • Benefits administration

    Administers enrollment, eligibility, ACA and COBRA work for the benefit plans the client sponsors.

  • HR administration

    Handles onboarding, documents, employee records and other day-to-day HR paperwork.

  • HR advisory support

    Gives access to HR professionals for employee relations, policies, handbooks and terminations.

  • Compliance support

    Tracks federal, state and local employment law changes and helps the client meet them.

  • Workers' comp administration

    Helps administer the client's own workers' compensation policy, such as premium reporting and claims.

  • HR and payroll technology

    Provides a platform for payroll, HR records, benefits enrollment and employee self-service.

How to choose ASO services

6 criteria · Requirements by company size · 5 red flags

An ASO is a service contract: you buy specific HR and payroll work while keeping the employer's obligations. Choose for what the fee covers, who does the work and what stays with your own team.

Ask every provider for the list of included services, the add-ons with their fees and a sample invoice for your headcount before you compare prices.

  1. Tax responsibility in writing

    With an ASO, payroll taxes are filed under your company's EIN. The IRS says a payroll service provider or reporting agent assumes no liability for its clients' employment tax duties, so a missed deposit is still yours.

  2. What the per-employee fee includes

    ASO fees are usually a per-employee monthly charge for the services you select, and many features are sold as add-ons, so two quotes with the same rate can cover different work.

  3. Benefits administration for your own plans

    You keep sponsoring your own benefit plans, so the ASO's value is in enrollment, eligibility, ACA and COBRA administration and carrier connections for those plans.

  4. Depth of HR advice

    Support ranges from an on-demand HR line to a dedicated HR business partner, and the difference shows in terminations, leave and handbook questions.

  5. Workers' compensation

    An ASO does not provide its own workers' compensation coverage: you keep your policy, and some ASOs help administer it.

  6. Technology and data ownership

    Your team and employees use the platform every day, and you keep the employer's records when you leave.

Requirements by company size

  • Small businesses

    • A base fee that covers payroll, tax filing and benefits administration
    • An HR line that answers real employee questions
    • A clear list of add-ons and their prices

    Watch out for

    • Minimum headcounts that exclude very small teams
    • Core payroll features sold as add-ons
    • Expecting PEO-style group benefits from an ASO

  • Mid-sized companies

    • Services you can add or drop as your HR team grows
    • Benefits administration that connects to your own carriers
    • Reporting and data export for finance and HR

    Watch out for

    • Per-employee fees that grow faster than the work you hand over
    • Advisory hours capped in the base fee
    • Platform limits for multi-state or multi-entity payroll

  • Enterprises

    • Modular services by function: payroll, benefits, HR or talent
    • Named specialists and business reviews
    • Clear terms on data, audit rights and service levels

    Watch out for

    • Overlap with work your in-house HR team already does
    • Separate fees for integrations and global payroll
    • Unclear ownership of tax notices and corrections

Red flags

  • The provider cannot say in writing who files and deposits your payroll taxes and how you can check each deposit.
  • The quote shows one per-employee rate but no list of what it includes.
  • The provider describes its service as an ASO but asks you to move employees onto its own EIN or its benefit plans, which is how a PEO works.
  • Exit terms restrict access to your own payroll history or tax records.
  • Savings claims are not tied to your actual headcount and services.

Frequently asked questions

Do ASO services publish their prices?

Of the 8 products compared, 1 publish a list price we can compare and 7 are quote-only (ADP Comprehensive Services, C2 Essentials ASO, Connor & Gallagher OneSource ASO, Easeworks ASO, and 3 more).

How we research

Ranked by the LeadChange Score, computed only from verified facts: capability coverage (30%), pricing and value (20%), integrations and API (15%), security (15%), fit and support (10%) and data confidence (10%), times a category fit. Products with too few verified facts are not scored yet and come last. Payment never changes a score or a position.

Read the full methodology

Facts, not impressions · Missing data is never assumed · Independent of revenue

  • Facts, not impressions

    Every input is a fact verified against vendors’ official documentation, with the date we last checked it.

  • Missing data is never assumed

    Unverified items are left out of the score and lower its coverage; below 60% coverage a product is not scored yet.

  • Independent of revenue

    Rankings never depend on whether a vendor pays us.

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