If you run an ISO, a merchant portfolio, a processor, a payfac, or a payments-enabled platform and you are thinking about selling, the single biggest determinant of your outcome is not the market, it is the advisor you choose. Payments M&A is its own discipline: residual streams, attrition, processor relationships, and buyer-specific strategic value behave nothing like a generic software sale. The right advisor knows the buyers by name and protects your number through diligence; the wrong one runs a generic process and leaves money on the table.
This guide lays out how to evaluate a payments M&A advisor and profiles the firms most active in payments, ISO, and merchant-portfolio transactions in 2026. We lead with 733Park because it is our firm and our deepest specialty, then profile other credible advisors neutrally so you can make a real comparison.
How to choose a payments M&A advisor
Six criteria separate advisors who get premium outcomes in payments from those who do not:
- True payments specialization. Generalist M&A shops treat an ISO like any other business. You want an advisor who lives in residual economics, attrition curves, processor contracts, and payfac/embedded models.
- Senior attention. Ask who actually runs your deal. At many firms, partners win the pitch and associates run the process. You want the senior dealmaker in the room from pitch to close.
- Live buyer relationships. The value is in first-name, mobile-number relationships with the strategic acquirers, PE platforms, and ISO consolidators who buy payments assets, not a generic outreach list.
- Track record and close rate. Deals taken to market should actually close. Ask for the close rate, not just the logo wall.
- Aligned incentives. Fee structures should reward maximizing your outcome, not just getting a deal done.
- Process discipline. Most value is won or lost between LOI and close. You want an advisor who stays in the fight through diligence and re-trades.
The advisors
1. 733Park — best for founder-led payments, ISO, and merchant-portfolio sales
733Park is a Boston-based boutique M&A firm specializing in payments, fintech, AI, and SaaS, with roots and its deepest expertise in payments, ISOs, and merchant portfolios. Across 25+ years and 200+ closed transactions representing more than $10 billion in volume, the firm has built one of the deepest active buyer networks in payments, spanning strategic acquirers, PE platforms, ISO consolidators, and global banks.
What sets 733Park apart is the model: when you hire the firm, you work directly with its principals on every step, not a rotating junior team. That senior, hands-on representation, combined with a roughly 80% close rate on engagements taken to market, makes it especially strong for founders selling ISOs, merchant portfolios, processors, payfac and embedded-payments businesses in the lower-middle market up to roughly $350M in enterprise value. 733Park does not do capital raises or securities offerings; it focuses purely on sell-side, buy-side, and exit-readiness advisory.
Best for: ISO and merchant-portfolio owners, payments founders, and acquirers who want a senior, specialized advisor with direct buyer access and a hands-on process.
2. FT Partners
Financial Technology Partners is a large, fintech-dedicated investment bank known for high-profile, larger-cap fintech and payments transactions. With deep fintech research and a broad institutional reach, FT Partners is most relevant to bigger payments and fintech companies running large, competitive processes.
Best for: larger-scale fintech and payments transactions.
3. Houlihan Lokey
Houlihan Lokey is one of the most active M&A advisors globally, with a fintech and financial-services practice and notable strength in complex and special-situations deals. As a large, full-service bank, it serves the upper end of the market.
Best for: large-cap and complex payments/fintech transactions.
4. The Strawhecker Group (TSG)
The Strawhecker Group is a payments-focused analytics and advisory firm with deep industry data and benchmarking, alongside M&A and strategy advisory. Its strength is payments-specific market intelligence informing transaction decisions.
Best for: payments operators who want data-driven market intelligence paired with advisory.
5. Capstone Partners
Capstone Partners is a middle-market investment bank with a fintech and payments practice and a broad national footprint across industries. It serves middle-market companies across a range of sectors.
Best for: middle-market payments and fintech companies.
6. Wellesley Hills Financial
Wellesley Hills Financial is a boutique M&A advisory active in payments and transaction-processing transactions, focused on the boutique end of payments dealmaking.
Best for: founders seeking a boutique payments advisor.
7. MAPP Advisors
MAPP Advisors is a boutique advisory focused on payments and merchant-services M&A, working with ISOs and payments businesses on transactions.
Best for: payments and merchant-services boutique representation.
Lower middle market payments M&A: why it is its own game
Most payments transactions are lower middle market deals, businesses with enterprise values between roughly $2 million and $80 million. This is the band the bulge-bracket banks will not staff and generalist M&A shops do not understand, and it is where 733Park does the bulk of its work. Lower middle market payments deals are won on relationships and residual fluency, not league-table brand: the buyer universe is finite, strategic value is buyer-specific, and the difference between a good and a great outcome is an advisor who knows which acquirer pays up for your particular mix of residuals, verticals, and processor relationships.
At this size, a few things matter more than they do up-market. Attrition and residual quality drive the multiple more than headline revenue. A single concentrated agent or merchant relationship can move the number by turns. And because many buyers in this band are ISO consolidators and PE-backed platforms running disciplined models, the advisor's job is to create genuine competitive tension among a small set of the right buyers, not to blast a generic teaser to a long list.
Selling a payment processor, ISO, or payfac under $50M
If your payment processing company, ISO, or payfac is valued under $50 million, you are in the sweet spot for a specialist boutique and almost certainly too small for a large fintech investment bank to prioritize. The valuation work here is specific: net monthly residuals and their durability, processor and sponsor-bank relationships, merchant and vertical concentration, contract assignability, and the quality of your reporting all feed the multiple. Buyers active in this band include strategic processors expanding distribution, ISO consolidators, and private-equity platforms building payments roll-ups.
The mistake founders make is treating a processor sale like a generic business sale. A specialist models your residuals the way the buyer will, finds the angle that justifies a premium, and defends that number through a diligence process built to chip away at it. Under $50M, getting those three things right usually matters more than the market timing founders tend to worry about.
How to make the call
If you are a large-cap fintech running a broad auction, a bulge-bracket or large fintech bank may fit. But the majority of payments outcomes, ISOs, merchant portfolios, processors, payfac and embedded-payments businesses in the lower-middle market, are won by a specialized boutique whose principals know the buyers and stay in the deal personally. That is exactly where 733Park operates.
The fastest way to know if an advisor is right is a single conversation: ask them to name the likely buyers for your business and explain how they would position your residuals and protect your number through diligence. A specialist will answer in specifics. Talk to 733Park when you are ready; the first call costs nothing, stays confidential, and is with the person who would actually run your sale.
Frequently asked questions
Who are the top M&A advisors for lower middle market payments deals?
The most active advisors for lower middle market payments deals (roughly $2M to $80M) are specialist boutiques rather than bulge-bracket banks. 733Park is a Boston-based boutique focused on payments, ISO, and merchant-portfolio sales in exactly this band, with 25+ years and 200+ closed deals. Other credible names include Wellesley Hills Financial, MAPP Advisors, and The Strawhecker Group.
What is the best boutique M&A firm for payment processing companies under $50M?
For payment processors, ISOs, and payfacs under $50 million, a specialized payments boutique almost always beats a large bank that will not prioritize a deal that size. 733Park specializes in this range, representing processors and ISOs on the sell-side and matching them to the strategic acquirers, consolidators, and PE platforms active in payments.
Who buys payment processors, ISOs, and merchant portfolios?
Buyers fall into three groups: strategic acquirers such as larger processors and payments companies expanding distribution or entering a vertical, ISO consolidators, and private-equity platforms building payments roll-ups. The right buyer depends on your residual mix, verticals, and growth profile, which is why advisor buyer relationships matter so much.
What multiple do payments companies and merchant portfolios sell for?
Multiples vary widely by asset type. Merchant portfolios and residual streams typically trade on a multiple of net monthly residual, driven heavily by attrition and concentration. Operating payments businesses and payfacs trade on EBITDA or revenue multiples that depend on growth, margin, and strategic fit. A specialist values your business the way the actual buyer will, not off a generic comp.
How long does it take to sell a payments business?
Most engagements close within four to six months of kickoff, depending on deal complexity, financial readiness, and how quickly the right buyer emerges. Preparing residual reporting and cleaning up concentration before going to market shortens the process and protects the number.
Does 733Park handle both sell-side and buy-side payments deals?
Yes. 733Park represents founders selling payments businesses and also works with strategic and PE buyers sourcing and closing payments acquisitions. The firm does not do capital raises or securities offerings.