Insero
Insero is a Rochester, NY-based accounting and advisory firm serving mid-market, nonprofit, government, and private clients across the Northeast and Great Lakes with audit, tax, outsourced accounting, transaction advisory, and HR services.
- Company typePrivate
- Founded1974
- HeadquartersRochester, United States
- Headcount101–250
- GTM typeB2B and B2C
- OfferingServices
What Insero does
Insero is a Rochester, New York-based regional accounting and advisory firm founded in 1972/1974, operating under an alternative practice structure with Insero & Co. CPAs, LLP providing licensed attest services and Insero Advisors, LLC providing tax and business consulting services. The firm employs 101-250 people across offices in Rochester and Ithaca and serves clients throughout the Northeast and Great Lakes regions (NY, NJ, PA, OH), with capability to serve clients nationally and on cross-border tax matters. It is led by CEO Nancy Catarisano and Executive Chairman Frank Longobardi.
The firm delivers a full-stack professional services platform organized around four practice areas: Audit & Assurance (financial statement audits, employee benefit plan audits, government and nonprofit audits, lease/ASC 842 and technical accounting advisory, SEC reporting and SOX support); Specialty Tax and Tax Planning & Compliance (business tax, SALT, R&D tax credits, international tax, and private-client services); Outsourced Solutions (client accounting services acting as a fractional finance function, outsourced HR advisory, and recruiting/staffing via Insero Talent Solutions); and Transaction Advisory Services (M&A support, financial due diligence, Quality of Earnings, and succession planning). The firm ranks in the top 1% of U.S. employee benefit plan auditors by plan assets audited (auditing 150+ benefit plans), is #216 on the Inside Public Accounting Top 500, and reports a 98% client recommendation rate and Net Promoter Score of 95. Technology stack includes integrated audit working-paper software, secure client portals (Citrix ShareFile, Sage Intacct), PCI-DSS compliant payment processing via CPACharge, and stated use of AI tools for process efficiency.
Revenue is generated primarily through custom engagement-based professional services pricing billed annually, with revenue mix across compliance (audit and tax), advisory (transaction support, technical accounting, CAS), and ancillary services (HR, recruiting). Insero received a strategic investment from Rallyday Partners in 2025 and has executed two acquisitions (DeMott & Smith CPAs in October 2025; Actel Advisory Group in May 2026) and joined the Aprio Alliance in March 2026, signaling a PE-backed roll-up posture targeting broader regional scale and higher-margin advisory capacity.
Insero firmographics
Firmographics- Name
- Insero
- Legal name
- Insero Advisors, LLC
- Website
- https://inseroadvisors.com
- Company type
- Private
- Founded year
- 1974
- Operating status
- Operating
- Headcount range
- 101–250 employees
- Short description
- Insero is a Rochester, NY-based accounting and advisory firm serving mid-market, nonprofit, government, and private clients across the Northeast and Great Lakes with audit, tax, outsourced accounting, transaction advisory, and HR services.
- Ownership category
- akta.pro rank
Where Insero is headquartered
LocationHeadquarters
- HQ city
- Rochester
- HQ country
- United States
- HQ region
- North America
Offices3 records
Markets served
Insero business model
Business model- GTM type
- B2B and B2C
- Offering type
- Services
- Cost components
- Personnel, Operations, Technology or R&D, Marketing or Sales, Others
Revenue model
- Audit & Assurance Services: Provides financial statement audits, employee benefit plan audits, nonprofit and government audits, agreed-upon procedures, and internal risk and control reviews for businesses and organizations.
- Tax Planning and Compliance: Comprehensive tax services including business tax planning, specialty tax services (R&D credits, cost segregation), state and local tax, international tax, and private client tax services.
- Client Accounting Services (Outsourced Accounting): Structured financial reporting, cash flow visibility, controller-level oversight, and fractional CFO services for growing organizations.
- Outsourced HR Services: HR advisory, compliance support, employee relations, staffing management, and project-based HR projects for organizations without dedicated HR leadership.
- Transaction Advisory Services: M&A advisory, financial due diligence, Quality of Earnings reports, transaction support, and succession planning for business transactions.
- Technical Accounting Advisory: Technical accounting consultation, accounting standard implementation, lease accounting support (ASC 842), and SEC reporting support for public companies.
Pricing tiers
| Model | Billing | Price |
|---|---|---|
| Other | Annual | Custom engagement-based pricing |
Go-to-market motion2 records
Distribution channels3 records
Marketing channels7 records
Insero product offering
Product offeringCore offering
Insero is a professional accounting and advisory firm that delivers audit, tax, and advisory services to businesses, nonprofit organizations, government entities, and high-net-worth individuals. It also offers outsourced client accounting and HR services through dedicated practices and operates a staffing subsidiary, Insero Talent Solutions, that supplies accounting and finance professionals.
Product overview
Insero is an award-winning regional accounting and advisory firm offering a comprehensive suite of professional services. The firm operates as a unified platform with distinct practice areas including Audit & Assurance Services (financial audits, employee benefit plan audits, lease accounting, technical accounting, public company solutions), Specialty Tax Services (SALT, R&D tax credits, business tax planning, international tax), and Outsourced Solutions (client accounting services, HR advisory, recruiting/staffing). The company also provides Transaction Advisory Services for M&A support and serves diverse industry verticals including manufacturing, nonprofit, private equity, real estate, government/education, and private clients. Insero operates as the brand name for Insero & Co. CPAs, LLP and Insero Advisors, LLC, with a subsidiary entity called Insero Talent Solutions for staffing services.
Differentiator
Problem solved
Functional benefit
Products and services
- Audit & Assurance Services Core audit and assurance services for businesses and nonprofit organizations across industry verticals.
- Employee Benefit Plan Audits Specialized audits of employee benefit plans for plan sponsors and administrators requiring ERISA-compliant audits.
- Lease Accounting Services Technical accounting support for ASC 842 lease accounting compliance for businesses with lease portfolios.
- Technical Accounting Solutions Technical accounting advisory for complex transactions and accounting standards application.
- Public Company Solutions Audit and advisory services tailored to public company reporting, SEC, and SOX compliance requirements.
- Specialty Tax Services Specialized tax services addressing complex or industry-specific tax situations.
- State and Local Tax (SALT) Services State and local tax planning, compliance, and controversy support for multi-state businesses.
- R&D Tax Credit Services Identification, calculation, documentation, and claiming of federal and state R&D tax credits.
- Business Tax Services Federal, state, and local business tax compliance and planning for corporations, partnerships, and LLCs.
- International Tax Services International tax planning and compliance for businesses and individuals with cross-border activities.
- Private Clients & Individuals Services Personal tax, estate, and advisory services for high-net-worth individuals and families.
- Client Accounting Services (CAS) Outsourced back-office accounting, bookkeeping, and financial reporting services for businesses.
- Outsourced HR Services Outsourced human resources support, including HR administration and compliance for client businesses.
- Transaction Advisory Services Advisory services for buyers, sellers, and investors supporting M&A and corporate transactions.
- Financial Due Diligence Services Buy-side and sell-side financial due diligence, including quality of earnings analyses, for M&A transactions.
- Manufacturing & Distribution Advisory Industry-specific audit, tax, and advisory services for manufacturing and distribution companies.
- Nonprofit Advisory Services Audit, Form 990, and advisory services for nonprofit organizations.
- Private Equity Advisory Transaction advisory and ongoing audit, tax, and advisory services for PE sponsors and their portfolio companies.
- Real Estate & Construction Advisory Industry-specific tax, audit, and advisory services for real estate developers and construction firms.
- Government & Education Services Audit and advisory services for government entities, municipalities, and public/private schools.
- Insero Talent Solutions Staffing and talent solutions subsidiary providing accounting and finance professionals to client organizations.
Quantifiable outcome
- 98% of clients recommend Insero, resulting in a Net Promoter Score of 95.
- +2 more outcomes
Companies that use Insero
Customer profileNamed customers6 records
Segments8 records
Ideal customer profiles6 records
Insero technology and API
TechnologyTechnology focussed No
API detail
- Has API
- No
- API docs
- API detail
Core technology
AI maturity
App detail
Integration4 records
Feature4 records
Insero partnerships and signals
Strategic signalPartnerships
Two partnerships are on record, tiered major and core.
- Actel Advisory GroupmajorInsero acquired Actel Advisory Group in May 2026 to strengthen its strategic business advisory services platform. This acquisition enhances Insero's capabilities in providing comprehensive advisory services to clients.
- Aprio AlliancecoreInsero Advisors is a member of Aprio Alliance, a national association of collaborative, growth-minded CPA firms. The affiliation provides access to leading expertise, resources, and best practices while preserving personalized service and local insight expected from an independent firm. Aprio Alliance supports Insero's commitment to exceptional client service and staying ahead of industry trends.
Scale indicators6 records
Recent moves5 records
Expansion highlights5 records
Insero competitors and assessment
Company assessmentBroad incumbents
- Aprio: National CPA and advisory firm and the namesake member of the Aprio Alliance that Insero joined in 2026. Aprio offers a broader national footprint and deeper specialty practices, positioning it as a senior alliance partner with overlapping service lines.
- CLA (CliftonLarsonAllen): National accounting firm serving private middle-market businesses, with strong advisory, audit, and tax practices. Comparable middle-market positioning to Insero with broader geographic coverage and similar PE-backed growth history.
- BDO USA: Top-tier national accounting firm with strong middle-market and private equity practice. Competes with Insero for mid-market audit, tax, and transaction advisory engagements, though at significantly larger scale.
- CBIZ: Public national professional services firm providing accounting, tax, advisory, and related services to middle-market businesses and individuals. Comparable diversified service model at meaningfully larger scale than Insero.
- RSM US: Largest US provider of audit, tax, and consulting services focused on the middle market. Directly comparable middle-market positioning to Insero with substantially greater national scale and PE practice depth.
- Plante Moran: Major US accounting and business advisory firm serving middle-market clients across audit, tax, technology, and consulting. Comparable client mix and service breadth, though larger and more diversified geographically.
- UHY International: Global mid-market accounting and advisory network serving middle-market clients across audit, tax, and consulting. Comparable client profile and service portfolio to Insero, with substantially broader geographic reach through member firms.
Direct peers
- Withum: PE-backed (BV Investment Partners) national accounting and advisory firm pursuing aggressive acquisition-driven growth. Closely comparable business model to Insero post-Rallyday investment — both are sponsor-backed CPA platforms executing roll-up strategies.
- The Bonadio Group: Rochester, NY-headquartered CPA and advisory firm of comparable size serving middle-market and nonprofit clients across audit, tax, and consulting. Same geography, same service mix, same middle-market target — the most direct peer.
- EFPR Group: Rochester, NY-based CPA and advisory firm of similar regional scale serving closely aligned middle-market, nonprofit, and government clients. Strong direct peer given shared geography and overlapping service lines.
Market position
Strengths5 records
Weaknesses5 records
Competitive moat5 records
Key risks6 records
Key highlights7 records
Customer concentration
Insero social profiles
Digital presenceInsero compliance and trust
Trust signalCompliance4 records
Insero financial estimates
Financial estimateRevenue estimate
Valuation estimate
Insero leadership team
Management profileNumber of profiles
Profiles7 records
Insero subsidiaries and ownership
Company hierarchySubsidiaries4 records
Insero funding detail
Funding detailFunding overview
Funding rounds
Investors
Funding detail is available on the Subscription and Enterprise plan.Contact sales →
Insero M&A and investment
M&A and investmentM&A3 records
Investments
M&A and investment is available on the Subscription and Enterprise plan.Contact sales →
Frequently asked questions about Insero
What does Insero do?
Insero is a professional accounting and advisory firm that delivers audit, tax, and advisory services to businesses, nonprofit organizations, government entities, and high-net-worth individuals. It also offers outsourced client accounting and HR services through dedicated practices and operates a staffing subsidiary, Insero Talent Solutions, that supplies accounting and finance professionals.
Is Insero a public or private company?
Insero is a private company. It is classified as venture growth investor backed and is currently operating.
When was Insero founded?
Insero was founded in 1974. It employs 101 to 250 people.
Where is Insero based?
Insero is headquartered in Rochester, United States, in the North America region.
How does Insero make money?
Six revenue lines are on record. Audit & Assurance Services are the primary driver. The others are tax Planning and Compliance, client Accounting Services (Outsourced Accounting), outsourced HR Services, transaction Advisory Services and technical Accounting Advisory.
Who are Insero's main competitors?
Broad incumbents on record are Aprio, CLA (CliftonLarsonAllen), BDO USA, CBIZ, RSM US, Plante Moran and UHY International. Direct peers are Withum, The Bonadio Group and EFPR Group.
Does Insero have an API?
No public API is recorded for Insero.