By Brandon Pham, Managing Partner
Executive summary
The U.S. accounting market is large, durable, and unusually fragmented, which is exactly why private equity has moved in with force. The sector represents a total addressable market of roughly $95B and grew at a 5.7% CAGR between 2022 and 2024, yet more than 99% of the country’s approximately 85,000 firms generate less than $10M in annual revenue. That long tail, combined with mandatory compliance demand and sticky multi-year client relationships, makes accounting one of the more attractive roll-up theses in business services today. For investors and operators, the question is no longer whether to build a platform but how to select one, integrate it, and defend margins as technology and a tightening labor pool reshape delivery.
A large, fragmented market built for roll-ups
At a $95B TAM growing 5.7% annually, accounting offers scale and steady expansion without the volatility of more discretionary professional services. The structural feature that matters most is fragmentation. With over 99% of roughly 85,000 firms below $10M in revenue, the supply of acquirable targets is deep, and valuations across the mid-market have been shaped by sustained PE interest. The opportunity extends beyond core tax and audit. Adjacent service lines, including advisory, technology services, and deal advisory, widen the pool of targets and the addressable spend per client. The practical implication is that platform selection requires discipline. The long tail rewards buyers who can identify a differentiated anchor and then execute a programmatic add-on strategy rather than chase volume alone.
Why demand holds through the cycle
Accounting demand is anchored by obligation, not preference. Clients have a recurring, non-negotiable need for tax, audit, and compliance work, and shifting federal, state, and local tax codes keep that demand persistent as firms work to avoid penalties and reputational harm. Core services are also more insulated from downturns than other advisory categories, since regulatory risk supports spend regardless of macro conditions. The relationships are exceptionally sticky, with average client tenures of 5 to 10 years in audit and managed services, and trust functions as the primary selection criterion. The financial signal is strong: 83% of global firms reported revenue growth from 2024 to 2025 and 79% reported improved profitability over the same period. Industry observers project 8 to 11% annual growth over the next three to five years, which positions quality firms as reliable cash generators and portfolio stabilizers.
Value creation, talent, and the risks to underwrite
PE value creation in accounting has followed two main paths: service line and cross-sell expansion, and geographic expansion. Cross-sell deepens share of wallet by consolidating spend into financial outsourcing, IT and systems integration, transaction advisory, and government work, all of which raise switching costs and lifetime value. Geographic plays exploit the parochial nature of CPA purchasing, where buyers select on trust and local relationships, so acquiring an established brand bypasses the long lead time of building reputation organically. Both strategies depend on retaining partners and local equity through integration. The central risk is talent. CPA enrollments have dropped 30% over five years and up to 75% of professionals are nearing retirement age, making retention and AI-enabled delivery essential. Cybersecurity and overlapping multi-jurisdiction compliance round out the risks that demand careful diligence.
Implications for investors and operators
The accounting roll-up thesis is sound, but returns hinge on execution. Prioritize platforms with a defensible anchor, strong technology service lines, and demonstrated partner retention, because mandatory-compliance revenue gives predictable cash flow over a hold period. Underwrite cross-sell potential conservatively by validating real client demand for new service lines before crediting synergy. In geographic expansion, protect local brand equity and rainmaker relationships, since fragmentation and turnover are the fastest ways to erode an integration thesis. Above all, build a clear plan for talent and AI-enabled delivery to offset the shrinking CPA pipeline and protect margins.
Contact us for the full report, which adds detailed market sizing, the competitive landscape, value-creation playbooks, representative Q3 2025 transactions, and the diligence question set we use to test a bid.