The Best Tax Advisors for Business Acquisitions: From a CPA’s Desk

Last Updated on June 11, 2026 by Ewen Finser

If you’re a founder preparing for a liquidity event or a private equity sponsor sizing up a platform acquisition, your standard CPA is not equipped to handle your deal. Trust me, I am that standard CPA, and I just don’t have the chops to give deals of that size what they deserve.

The reason for this is that general tax compliance is about looking backward: filing returns, ensuring regulatory adherence, and keeping the IRS at bay. Meanwhile, M&A tax advisory is entirely forward-looking (value creation and preservation), which most CPAs can do but don’t excel at. 

That’s why, for mid-market and enterprise deals, choosing the right tax advisor is as critical as choosing the right investment bank or legal counsel. So let’s jump into who the players are and what they do.

At a Glance

	Deal Size Sweet Spot	Fee Level	Industry Specialization	Post-Close Support	Best For
Big Four (Deloitte, PwC, EY, and KPMG)	$1B+	Very High	Broad/Global	Minimal	Buyers (mega-cap / multinational)
HCVT	$20M – $500M	High	Pass-through entities	Minimal	Buyers & sellers (PE/founders)
CohnReznick	$20M – $500M	Moderate to High	Renewables, healthcare, tech	Minimal	Buyers (regulated industries)
Pillar Advisors	$20M – $500M	Moderate	Generalist	Core offering	Buyers & sellers (lean finance teams)

1. The Big Four: Deloitte, PwC, EY, and KPMG

No M&A tax advisory list is complete without acknowledging the Big Four: Deloitte, PricewaterhouseCoopers (PwC), Ernst & Young (EY), and KPMG. Unmatched in terms of global scale and sheer headcount, these companies are best suited for mega-cap deals, Fortune 500 integrations, and highly complex cross-border transactions. When a multi-billion-dollar publicly traded conglomerate acquires a foreign competitor with subsidiaries in forty different tax jurisdictions, the Big Four are the only firms with the physical footprint and hyper-specialized roles to handle the structuring.

They excel at identifying fatal tax exposures such as unrecognized historic sales tax liabilities, aggressive misclassification of independent contractors, or poorly documented R&D credits that won’t survive an audit. For buyers, they provide incredibly dense, exhaustive tax structuring decks that map out every conceivable integration scenario.

In short, if you engage one of these firms, you aren’t just getting a tax partner; you are getting a specialized state and local tax (SALT) team, an international transfer pricing team, a compensation and benefits tax team, and a dedicated financial modeling desk.

But for middle-market deals (typically defined as transactions with enterprise values between $20M and $500M), the Big Four can be a double-edged sword. 

For one, the fee structure is simply astronomical. Second, your mid-market deal is simply not their priority — while a senior partner will pitch the engagement, the actual tax due diligence and modeling will just be pushed down to associates and managers. Finally, they operate within strict risk-management parameters. Their tax structuring memos are notoriously conservative and heavily caveated; they’ll give you an encyclopedia of potential tax risks, but they often leave it up to the buyer’s internal finance team to figure out how to operationalize those findings into the financial model or the working capital peg.

Pros:

• Unrivaled global footprint with dedicated teams for every tax specialty (SALT, transfer pricing, comp & benefits, financial modeling)
• Only firms capable of handling 40+ jurisdiction cross-border deals end-to-end
• Exhaustive diligence coverage — if there’s a tax exposure, they’ll find it
• Deep bench of hyper-specialized talent that no mid-market firm can replicate

Cons:

• Fee structures are astronomical — often prohibitive for anything under $500M
• Senior partners pitch the deal, then hand it off to associates and managers
• Middle-market engagements are simply not a priority within their book of business

Best for:

The Big Four really are for multi-national corporations, mega-cap private equity funds, and deals exceeding $1B in enterprise value where cross-border regulatory compliance is the primary hurdle.

2. Holthouse Carlin & Van Trigt (HCVT)

HCVT has carved out a reputation as a go-to firm for middle-market private equity sponsors, family offices, and high-net-worth founders. They punch far above their weight class because they don’t bother trying to be everything to everyone; they focus relentlessly on complex, high-stakes tax structuring.

Their superpower lies in pass-through entities. The vast majority of middle-market targets are structured as S-Corporations or LLCs (taxed as partnerships), which present unique M&A challenges, particularly when private equity gets involved.

When a PE sponsor wants to acquire an S-Corp, they typically require a step-up in tax basis to amortize the purchase price. However, PE funds are often structured as partnerships with corporate partners, meaning they cannot legally own S-Corp stock without blowing the target’s S-election. HCVT is elite at navigating these exact scenarios.

They’re also highly adept at sell-side tax readiness. HCVT will step in months before an LOI is signed, clean up a founder’s cap table, execute pre-transaction estate planning, and model out exact after-tax proceeds under various purchase price scenarios.

However, HCVT is a pure-play tax and audit firm. While their M&A tax structuring is world-class, they remain fundamentally an accounting firm. Once the deal closes, the transition from transactional tax planning to operational finance is largely on your shoulders.

Pros:

• Best-in-class technical expertise on pass-through entity structuring (S-Corps, LLCs, partnerships)
• Strong sell-side readiness practice — will engage months before LOI to prep the cap table and model after-tax proceeds
• Punches well above its weight for a non-Big Four firm
• Deep relationships in the middle-market PE ecosystem

Cons:

• Pure-play tax and audit firm — post-close operational finance support is not in their lane
• Less suited for buyers acquiring C-Corps or targets in highly regulated industries

Best for:

HCVT makes the most sense for lower-middle and middle-market private equity sponsors, real estate syndicators, and founders of pass-through entities who need highly technical structuring for rollover equity.

3. CohnReznick

CohnReznick bridges the gap between the boutique feel of regional firms and the massive resource pool of the Big Four. What separates CohnReznick in the M&A tax space is their commitment to industry specialization, particularly in renewable energy, healthcare, and technology.

This is vital since, in M&A, generic tax advice is dangerous. After all, the tax attributes of a SaaS company carrying massive NOLs under Section 382 are entirely different from a renewable energy developer relying on ITCs. CohnReznick understands this and organizes its transaction tax teams by industry.

For buyers, CohnReznick provides an excellent, holistic suite of transaction advisory services. They don’t just look at tax in a vacuum; their teams integrate tax diligence with QoE reports, IT due diligence, and valuation services. If a buyer is looking to acquire a target with complex contingent earn-outs, CohnReznick’s valuation practice works directly with their tax partners to determine how those earn-outs will be treated and the resulting tax liabilities.

They are also incredibly strong in SALT due diligence. As more companies adopt remote workforces, nexus laws have created massive, hidden sales tax liabilities that they can pick apart. CohnReznick excels at identifying these exposures during due diligence and negotiating VDAs to clear the risk before the deal closes.

While their industry expertise is formidable, CohnReznick still operates on a traditional advisory model. They deliver excellent reports, memos, and structuring advice, but at the end of the day, they’re an external consultant. The implementation of their advice requires a competent internal finance team on the buyer or seller side to absorb the findings and execute them post-close.

Pros:

• Industry-specialized transaction teams (renewables, healthcare, tech) — not a generalist shop
• Single-firm integration of QoE, tax diligence, IT diligence, and valuation
• Exceptional SALT and nexus expertise, especially relevant for remote-workforce targets
• Better fee structure than the Big Four while offering comparable depth in their focus industries

Cons:

• Traditional advisory model — strong on deliverables, weak on implementation
• Less technically specialized than HCVT for complex pass-through restructuring

Best for:

This firm is best for buyers acquiring targets in highly regulated or incentive-heavy industries (like renewables or healthcare) who want a single firm to handle both QoE and tax due diligence.

4. Pillar Advisors

Pillar treats M&A tax advisory not as a siloed consulting deliverable, but as a core component of a mid-market company’s broader financial engine.

This fills a very common vacuum in traditional M&A tax advisory: the hand-off. The Big Four, HCVT, and CohnReznick will write a brilliant 80-page tax structuring memo, deliver it to the buyer/seller, collect their fee, and exit the stage. 

But who actually implements the structure? Who ensures that the opening balance sheet correctly reflects the tax allocations? Who updates the post-close financial model to account for the new debt schedule and amortization?

Pillar Advisors aims to solve this by serving as a white-glove, fractional financial executive team that bridges the gap between tax structuring, corporate finance, and post-close accounting. They’ll help determine what makes sense in terms of the acquisition and then lead the project 6 months before the LOI comes through — and 6 months after the deal has closed.

They provide seamless pre- and post-close integration for both founders and buyers. For sellers, Pillar acts as the tip of the spear by cleaning up financials, optimizing working capital, and defending EBITDA adjustments. For buyers, they eliminate day 1 hurdles by translating the tax structure into a comprehensive 100-day plan, accurately embedding tax allocations into accounting systems, and tightly managing working capital to prevent post-close cash disasters.

Just note that Pillar Advisors is fundamentally built for execution and ongoing operational partnership, not one-off consulting mandates. If you are a buyer or PE sponsor who simply needs a standalone QoE report to check a box for a lender, or a point-in-time tax structuring memo with a hard end-date, Pillar is likely not the right fit.

Pros:

• Solves the hand-off problem — pre- and post-close execution is their core offering, not an afterthought
• Functions as a fractional CFO/finance team, eliminating the need for sophisticated internal M&A finance capabilities
• Integrated approach spans tax structuring, corporate finance, and post-close accounting
• Ideal fit for lean organizations that can’t absorb an 80-page memo and run with it independently

Cons:

• Not the right call for standalone, point-in-time engagements (QoE report, one-off structuring memo)
• Less technically deep than HCVT for highly specialized pass-through restructuring scenarios

Best for:

Pillar makes sense for mid-market founders, independent sponsors, and PE-backed portfolio companies who need M&A tax advisory backed by the execution capabilities of an elite, integrated finance team.

How to Choose the Right Advisor for Your Transaction

Selecting the right tax advisor for an acquisition comes down to matching the firm’s structural model to your internal capabilities and deal size.

• If your deal is over $1 billion, involves multiple sovereign tax jurisdictions, and your internal tax department has 50 people, default to the Big Four. The fees are astronomical, but global risk mitigation is necessary.
• If you’re a middle-market PE firm executing a highly complex partnership restructuring or S-Corp Reorganization and you have a strong internal CFO to manage the integration, HCVT brings unparalleled technical firepower.
• If you are acquiring in a niche sector like renewable energy or real estate and you want a single firm to handle both QoE and SALT due diligence under one roof, CohnReznick is an exceptional choice.
• If you’re a mid-market buyer or seller who lacks a sophisticated, M&A-fluent internal finance department, hiring a traditional firm is a risk. You will get a great memo, but poor execution. In this scenario, Pillar Advisors is the clear choice.