How to integrate an accounting firm after an acquisition

The deal gets a data room, a lawyer, a deadline and everybody's attention. The integration gets a Monday. That is backwards, because the revenue you just paid for does not transfer on completion. It transfers when the people who deliver the work decide to stay, and when the clients never notice anything happened.

Listen to the full episode: How To Succeed With M&A Integration Before The Deal Is Done.

Screen for fit before you issue the letter of intent

Integration starts before the paperwork. Ashley Rhoden, Chief Operating Officer at High Rock Accounting, was acquired once as an employee and led four firm integrations at a previous firm. On The Firm's M&A Diaries, October 2025: "integration for me doesn't start at closing. It actually starts before the LOI or the letter of intent is actually ever even issued."

Her screening tool mirrors the ideal client profile. She calls it an ideal business profile, and "your IBP framework is really going to cover the cultural alignment." Write yours down before you go looking, then test each target against five things:

• Cultural alignment. Does this firm fit your culture?
• Operational compatibility. Are systems and processes compatible?
• Team dynamics. Left open on her list; I would read it as who runs the work day to day.
• Compensation models. Do the pay structures line up?
• Service delivery. Do the two approaches match?

People and culture rank above systems

Asked to rank the integration categories, Rhoden did not hesitate: "people and culture is going to be your most critical aspect." Her reasoning is blunt. "Without the people, you have nothing." Systems and technology came second, then client relationships, operations and process.

Rhoden's point about first time buyers, paraphrased: the excitement gets them, so they perfect the financial diligence and skip the human work. The fix is a budget rule: "as much investment time that people put into the buying process, they need to do the same amount or more in the integration process." It bites harder in accounting because of who the profession attracts. On Rhoden's read, "they didn't go into accounting because they love change" and a team like that does not respond well to a surprise, which makes everything below a retention question rather than a courtesy. Our piece on safeguarding culture as your firm grows covers the same problem outside a deal.

Turn diligence into a 100 day checklist with named owners

The bridge between diligence and delivery is one document. As Rhoden describes it: "Your 100-day checklist is literally just, OK, here's what we learned in due diligence."

She does not leave ownership vague: "in my due diligence, I created a RACI chart." It maps who is responsible, who is accountable, who is consulted and who is merely informed, across five named leads: HR and people, operations, client, IT systems, and finance. Spell out the work, because your leads may never have done this before.

My recommendation: put that checklist in front of the seller before close and ask them to mark it up. They know which system is load bearing and which one you can rip out in week two. The post completion integration lessons from John Holliday make the same case.

Scale is no excuse to skip it. Rhoden's line: "A firm is a firm and acquisition is acquisition." She has run both ends of the range: "I integrated a firm that was five employees and I integrated a firm that was 45 employees."

Day one and the first week

Day one has a very short list. In Rhoden's words, "day one priorities for me is payroll must be perfect." System access has to be seamless and daily operations undisrupted. On why that first pay run carries the weight: "That first payroll is critical to your success with these new employees." Test it before completion, not on the day.

Days one to seven are a foundation period, not a change window: orientation, concerns addressed as they surface, rhythms set, real capacity assessed. Client contact starts here too, narrow and reassuring. Her instruction: "You're contacting your top 20% of high value clients." The script is straight reassurance: "Nothing's changing." and "It's just business as usual."

Days 31 to 60, then a standing cadence

By the second month you move on the systems that matter to you, get proactive with client and vendor communication, and start measuring how the team feels. That last one is the gap Rhoden sees most often. "You're also measuring employee satisfaction. That is something that I think is often missed in integration." Then make it recurring, on Rhoden's cadence: "Every 30 to 60 days, you should be touching base and making sure that your employees are satisfied". Give it an owner from your RACI, because a measure with nobody's name against it quietly stops happening.

Tell the key leaders before close, even when you cannot tell everyone

Rhoden learned this rule from the wrong side of it. "We were told the day that the paperwork was signed that, hey, you're being acquired and you have 24 hours to sign your employment agreement." Her standard now is to answer the questions before people finish forming them: "you have to be 10 steps ahead of their thinking."

Sellers resist, reasonably: a deal that leaks and then dies takes the team and the client relationships with it. Her compromise: "It could just be the key employees or the leadership team that you're bringing over and getting their buy-in before the actual close." Staff look to those leaders for reassurance, so buying their trust early does most of the work. Pulling them into diligence also gets you institutional knowledge an owner who has stepped back cannot give you.

Then over communicate in more than one format, because "everyone learns and communicates differently." Publish a timeline covering what changes in the first six months and what changes in the six after that. None of this is legal advice, and rules on informing staff about a change of employer differ by country, so take local advice on the sequence.

Change internal systems early, client facing things late

The question that decides your first six months is whether the client can see the change. Rhoden's rule: "you need to minimize the client changes as much as possible." No new chat tool, no new way of sending receipts. Spend your appetite internally instead: "You can mess with your employees a little bit more than you can mess with your clients."

Stack consolidation belongs on that internal list, and it is an operations question. Rhoden's own worst call was leaving it fragmented: "one of the biggest mistakes that we actually made was that we were diversified across too many tech stacks." Information ended up scattered across systems that would not talk to each other, so the data she needed for decisions was unusable. Decide early which system is the single source for each function, then migrate on a schedule the client never sees. The lessons from tough acquisitions land in the same place.

Treat the brand as a phased decision

Rhoden is straight about the limits of her experience here: "I have not actually done a brand change at acquisition." She rolled acquired firms under an umbrella instead, and names the cost of doing it loosely: clients confused, because "They're getting an invoice from the parent company, but all the communication is coming from the company that they just acquired." Staff were unsure what to call themselves.

The timing she used: "Our approach was that we would roll the companies in after one year and change the brand after one year." Both failure modes are real. Vagueness on day one confuses people, and a forced rename creates chaos, because email addresses and everything tied to them cannot move that fast. Pick a date, say it out loud, and make sure whoever answers the phone knows which name to use.

Keep the seller aligned, because they keep their influence

The seller keeps influence either way. As Rhoden said: "those employees, I guarantee, have a relationship with that seller." If the seller is quietly briefing against your direction, you get unhappy staff, and "when you have negative employees, guess what happens? You have client churn."

The alignment work is commercial, not social. Rhoden's test for a counterparty is unsophisticated: "Make sure that you can be friends. And if you can't be friends, then you should not buy their company." Underneath it sits her summary of what a firm sells: "we are selling a relationship." Sellers weighing their own side should read our guide to building a firm you can sell or step away from.

Structure is a lever goodwill does not give you. Rhoden points at the deal itself: "You want to make sure that there's an earn out period or, you know, there's different ways that you could structure it and be creative with the deal to make sure that you get that seller alignment from the very beginning."

As Rhoden put it: "the deal is not the hard part. It's the integration that's the hard part."

Frequently asked questions

Who should own integration if we do not have a COO?

Someone with authority over operations and no client delivery targets. Expect it to take most of one person's attention for a quarter. If nobody can be freed up, name an owner per workstream and give one person the standing meeting. Not the deal lead, who gets pulled onto the next transaction.

We already completed and never built a plan. Is it too late?

No, but work in the order of what is bleeding. Confirm payroll and access are clean, call the largest clients before someone else does, then start the employee check ins. Build the checklist retrospectively and accept you will be asking late what diligence should have told you.

The seller will not allow any communication before close. What is the fallback?

Plan a heavier day one. Have the paperwork, orientation and timeline ready the moment it is signed, give people longer than 24 hours to read what they sign, and get your leader in front of the team that week.

Does any of this scale down to a very small acquisition?

The checklist and the named owners stay. A five person team can be briefed in one room, which is faster and less forgiving: one unhappy person is a fifth of the capacity you bought.

How do we know the integration is actually working?

Pick measures you can read monthly: staff satisfaction on the 30 to 60 day cadence, retention of the clients you called in week one, and whether the client facing experience has changed at all.