The brutal reality: most integration checklists you'll find online are built for single, large-scale corporate M&A-not for roll-ups doing three to five acquisitions a year. They're either too generic (vague platitudes about "aligning cultures") or too exhaustive (600-line spreadsheets no one maintains past week two). Neither helps when you're balancing Day 1 operations at a newly acquired pest control business whilst your CFO is chasing down bank account details and your IT director is fielding password reset requests from sixteen different email domains.
This checklist is built from patterns we've seen work across acquisitions in facilities management, industrial services, healthcare, and home services. It reflects what actually works: a scannable, phase-by-phase execution roadmap that covers every critical workstream-Day 1 readiness, communication, HR, finance, IT systems, operations, legal, and vendor management-without the fluff. And crucially, it's structured around the three integration levels (High-Touch, Medium-Touch, Low-Touch) so you can prioritise ruthlessly and match integration depth to strategic intent. This isn't about closing deals. It's about making them work.
Why Most Integration Checklists Fail (And What to Do Instead)
Here's what kills most checklists:
Generic One-Size-Fits-All Thinking. A tuck-in acquisition with three technicians needs a radically different plan than a 150-person strategic buy with overlapping geographies. Yet most templates treat them identically.
No Accountability or Ownership. A list of tasks without names, dates, and decision rights becomes wallpaper. "Align payroll systems" sounds simple until you realise no one's decided whether to migrate the target onto your platform or run dual payroll for six months.
IT Treated as an Afterthought. IT dependencies cascade everywhere-finance can't consolidate reporting without data access, operations can't track jobs without CRM visibility, HR can't onboard without email-yet IT workstreams are often buried halfway down the checklist with no resourcing plan.
Cultural and Change Management Skipped. You can migrate systems faster than people change behaviour. A checklist that ignores communication cadence, role-based training, and digital champions will deliver technical compliance but operational chaos.
What to Do Instead:
- Customise ruthlessly. For every acquisition, decide upfront: High-Touch (full consolidation), Medium-Touch (financial and email spine, flexible operations), or Low-Touch (minimal integration, maximum autonomy). Your checklist should flex accordingly.
- Assign a single owner to every task. Every line item needs an owner and a due date. "IT Team" isn't specific enough: "Sarah (IT Director) by 15 March" is.
- Build iterative reviews into the plan. Week 2, week 6, week 12-schedule checkpoint calls to surface blockers, update timelines, and reprioritise. Integration plans are living documents, not static PDFs.
- Track dependencies explicitly. If finance reporting depends on CRM data migration, note that. If vendor rationalisation depends on contract reviews, note that. Make the sequencing visible.
Pre-Close: Lock Down Your Integration Blueprint
Integration starts before the ink dries. The decisions you make-or defer-in the weeks before close will dictate how smoothly Day 1 unfolds and how quickly you can turn the lights on for consolidated reporting.
Finalise Deal Economics and Synergy Targets
- Define synergy targets with precision. Break down revenue synergies (cross-sell, pricing uplift) and cost synergies (vendor consolidation, headcount reduction, system rationalisation). Assign an owner and a timeline for each.
- Build a synergy tracking model. Use a simple spreadsheet: Target | Owner | Baseline | Current Status | Realised £ | Date Achieved. Update it monthly.
- Agree on KPIs that matter. For roll-ups, the priorities are usually: consolidated revenue visibility within 30 days, unified payroll within 60 days, CRM/ERP migration within 90–120 days, and vendor spend visibility within 45 days.
Conduct Technical and Operational Due Diligence
- Inventory all systems. What software does the target use? CRM, ERP/accounting, payroll, email, file storage, operational tools (scheduling, dispatch, job tracking), HR systems, compliance/safety platforms. Who are the admins? What's the contract status?
- Assess data quality early. Don't wait until migration day to discover that 30% of customer records are duplicates or that job histories aren't timestamped. Run a data quality audit now.
- Gather employee data. Full census: names, roles, email addresses, reporting lines, start dates, compensation bands. You'll need this for payroll setup, email provisioning, org chart planning, and communications.
- Map workflows and integrations. How do they dispatch jobs? How do invoices flow from job completion to accounting? What's integrated, what's manual, what's Excel? Identify mission-critical workflows that cannot break on Day 1.
Define Your Integration Model and Governance Structure
- Choose your integration level. High-Touch (full system consolidation, single ERP/CRM, unified processes-timeline 3–6 months). Medium-Touch (unify finance, email, HR: keep operational systems flexible-timeline 2–3 months). Low-Touch (connect only what's needed for financial visibility and basic security: leave operations autonomous-timeline 2–4 weeks). Document the decision and share it with all stakeholders so expectations are clear.
- Build your integration team and governance structure. Who's the Integration Lead? Who owns finance, IT, operations, HR, legal, communications? Create a RACI matrix. Schedule a weekly integration steering call (30–45 minutes, standing agenda: progress against checklist, blockers, decisions needed).
- Draft a high-level integration roadmap. Pre-Close | Day 1–30 (stabilise) | Day 31–100 (execute core workstreams) | Day 101–180 (embed and optimise). Share it with the acquired leadership team before close so they know what's coming.
Day 1–30: Stabilise, Communicate, and Validate
The first month is about ensuring continuity, avoiding panic, and building trust with the acquired team. You're not trying to transform everything overnight: you're proving the business keeps running whilst the systems change.
Secure Critical Systems and Establish Operational Continuity
- Resolve Day 1 IT and finance access. Platform finance team needs read-only access to target accounting system (for reporting), admin access to bank accounts (for cash management), and visibility into payroll systems. IT needs admin credentials for email, file storage, and any cloud platforms.
- Set up lockbox and banking arrangements. If the acquisition uses separate bank accounts (common in the first 60–90 days), establish daily reporting so your CFO can see cash flow. If you're migrating to platform accounts, coordinate with your bank and ensure standing orders, direct debits, and supplier payments don't break.
- Validate payroll continuity. Confirm next payroll run date, who's processing it (target's payroll bureau or yours), and that employee records are accurate. Payroll problems on Day 1 erode trust faster than anything else.
- Run a Day 1 IT health check. Are systems up? Can employees log in? Are customer-facing tools (CRM, dispatch, scheduling) working? Assign someone to monitor the IT helpdesk closely for the first week and resolve issues within hours, not days.
- Develop IT assumptions and risk register. What legacy systems are we inheriting? What's end-of-life or unsupported? What's the plan for auditing and mapping before we touch anything?
Launch Change Management and Communications Programme
- Draft and deliver Day 1 communications. Separate messages for: acquired company leadership (detailed, operational), acquired company staff (reassuring, practical), platform company staff (context, how to support), and customers (if customer-facing changes are imminent). Tone: calm, specific, no hyperbole.
- Host a Day 1 leadership meeting. Agenda: welcome, integration roadmap overview, governance structure, key contacts, Q&A. Make it a conversation, not a lecture.
- Create a stakeholder communications matrix. Who needs updates, how often, and via what channel? Weekly email to acquired leadership, fortnightly all-hands for acquired staff, monthly update to platform exec team.
- Identify digital champions. Within the acquired company, who are the respected operators, the people others turn to when they have questions? Recruit them early as informal adoption ambassadors. Give them advance context on changes and ask for their input.
- Cascade priorities clearly. For the first 30 days, the acquired company's job is: keep customers happy, keep operations running, provide information when asked, flag problems immediately. They're not expected to learn new systems yet.
Day 31–100: Execute Core Integration Workstreams
This is where integration work accelerates. You've stabilised, communicated, and validated your roadmap. Now you execute across every workstream in parallel, with clear sequencing and dependency management.
Consolidate Systems and Migrate Data
- Email and file migration first. Move acquired company onto your email platform (Google Workspace or Microsoft 365). Migrate files to your standard (Google Drive or SharePoint). This is foundational for communications, collaboration, and security. Timeline: weeks 4–8. Note: be mindful of the conversion trap-files created in Google Docs break when forced into Microsoft Office, and vice versa. Test before mass migration.
- CRM/ERP unification next. For High-Touch integrations, migrate customer, job, and financial data into your platform CRM and ERP. For Medium-Touch, connect systems via API or reporting layer but defer full migration if the target's CRM is superior for their vertical. For Low-Touch, leave systems separate but ensure you can extract financial data for consolidated reporting. Timeline: weeks 6–14.
- Assess and migrate operational tools. Scheduling, dispatch, job tracking, quoting-does the target use tools you don't? Are they better than yours? If yes, consider adopting theirs (even for platform operations). If no, plan migration but phase it carefully to avoid operational disruption. Timeline: weeks 8–16.
- Run data quality validation before and after migration. Pre-migration: identify duplicates, incomplete records, formatting issues. Post-migration: validate record counts, test key workflows, confirm reporting accuracy. Don't assume data will migrate cleanly: it won't.
- Rationalise software licenses and subscriptions. Cancel duplicate tools, consolidate vendor accounts, and negotiate volume discounts where possible. Assign finance or IT to own this: it's low-hanging cost synergy but easy to forget.
Harmonise Processes and Rationalise Vendors
- Align accounting policies and chart of accounts. Your CFO needs a unified chart of accounts to produce consolidated financials. If the target uses different revenue recognition, cost allocation, or depreciation policies, reconcile them now.
- Consolidate vendor lists and procurement processes. Pull a full vendor spend report from the target. Identify: duplicates (e.g., both companies use different IT support providers), opportunities for volume consolidation (insurance, fleet, uniforms, supplies), and contracts up for renewal. Assign procurement or ops to rationalise.
- Standardise operational processes (selectively). For High-Touch integrations, align job workflows, quoting, invoicing, and customer onboarding. For Medium-Touch, align finance and HR processes but allow operational flexibility. For Low-Touch, document their processes and leave them largely unchanged.
- Review and update compliance and safety protocols. Ensure the target is operating under your H&S policies, insurance coverage, and regulatory compliance frameworks (especially for healthcare, facilities, and industrial services). Audit certifications, training records, and incident logs.
Align Teams and Standardise Reporting
- Build unified org charts. Who reports to whom, now? Where are there overlaps or gaps? Make reporting lines clear and publish them.
- Plan for redundancies (if needed). If there are overlapping roles (e.g., two finance managers, duplicate admin functions), make decisions early and execute them humanely. Dragging out uncertainty demoralises everyone.
- Launch role-based training for new systems. Don't do generic training ("here's how CRM works"). Do role-specific training ("here's how you, as a service coordinator, create a job, assign a technician, and invoice a customer"). Build short how-to videos and quick-reference guides. Offer live Q&A sessions, not just recorded webinars.
- Deploy unified reporting dashboards. Your executive team needs real-time visibility: revenue by business unit, job completion rates, gross margin, cash flow. Build (or buy) dashboards that pull from all systems-legacy and new-until migration is complete. For practical frameworks, our integration playbook covers reporting strategies in detail.
- Track attrition closely. Integration is stressful. Monitor who's leaving, especially high performers and customer-facing staff. Exit interview every departure to understand whether it's integration-related or coincidental.
Day 101–180: Embed, Optimise, and Track Value Realisation
By day 100, most core migrations should be live. Now the focus shifts to adoption, optimisation, and ensuring synergies aren't leaking.
Deploy Hypercare and Monitor Adoption
- Run a 1–2 week hypercare period post-migration. After any major system go-live (email, CRM, ERP), provide intensive support: dedicated Slack channel or helpdesk queue, daily check-ins with acquired leadership, rapid response to issues. The goal is to catch problems before they compound.
- Measure adoption, not just completion. Don't just track "CRM migration: complete." Track: What % of users are logging in daily? Are jobs being created in the new system or are people reverting to spreadsheets? Are invoices flowing correctly? Use system analytics and spot-check workflows.
- Iterate training and documentation. Based on support tickets and user feedback, identify gaps. Update guides, record new how-to videos, run refresher sessions. Adoption isn't a one-time event: it's a process.
- Conduct a post-integration retrospective. What went well? What took longer than expected? What would we do differently next time? Document lessons learned and update your M&A integration checklist template for the next acquisition.
Measure Synergy Capture and Close Out Integration Debt
- Update your synergy tracking model. For every target you set pre-close, what's been realised? What's delayed? What's at risk? Report this to your board or PE sponsor monthly.
- Quantify integration debt. What did we defer? Legacy systems still running? Processes not yet standardised? Vendor contracts not yet consolidated? Document it, prioritise it, and schedule closure. Integration debt compounds: the longer you wait, the more expensive it becomes.
- Close out project financials. What did integration actually cost (IT, consulting, contractor hours, software, severance)? Compare to budget. Understand variances.
- Celebrate wins with the acquired team. Integration is hard work. When milestones land-consolidated reporting live, CRM migration complete, first unified all-hands-acknowledge it. Thank people. Build momentum for the next phase.
- Prepare for the next acquisition. Update your playbook, refine your templates, and brief your team. If you're doing multiple acquisitions a year, choosing the right resourcing model -whether in-house, contractors, or a partner like us-becomes critical.
Your M&A Integration Checklist Template: What to Customise for Every Deal
No two acquisitions are identical. Tailor your checklist by:
Deal Size and Complexity
- Tuck-in (<10 employees): Focus on email migration, payroll consolidation, and basic financial reporting. Skip elaborate governance: a single integration lead and weekly check-ins are enough.
- Strategic buy (50–200 employees): Full checklist. You'll need workstream leads, formal governance, and phased execution across all workstreams.
Integration Level
- Low-Touch: Trim the checklist to essentials-bank access, financial reporting extraction, email/security baseline, light communication. Leave most operations autonomous.
- Medium-Touch: Finance, email, HR, and reporting get full treatment. Operational systems and processes stay flexible. Vendor rationalisation is selective.
- High-Touch: Execute the full checklist. Every system, every process, every vendor gets scrutinised and consolidated.
Industry and Regulatory Context
- Healthcare or regulated industries: Add compliance workstreams-CQC registrations, insurance updates, clinical governance, data protection impact assessments.
- Field services (pest control, HVAC, landscaping): Prioritise dispatch and scheduling systems, vehicle fleet integration, supplier consolidation (uniforms, chemicals, parts).
Geographic and Payroll Complexity
- Multi-country acquisitions: Factor in country-specific payroll, employment law, VAT/tax registration, banking arrangements, and data residency rules. Timeline extends by 4–6 weeks.
Measurable Objectives and KPIs
For every acquisition, set three to five non-negotiable success metrics:
- Consolidated financial reporting live by day 30
- Email and file migration complete by day 45
- CRM/ERP migration live by day 90
- Vendor spend visibility and first wave of rationalisations by day 60
- Voluntary attrition <5% in first 120 days
Track them weekly. When you miss a milestone, understand why and update the plan.
Interdependencies and Sequencing
Make dependencies explicit in your checklist:
- Finance reporting depends on → read access to target accounting system → bank account setup
- CRM migration depends on → data quality audit → user training → hypercare resourcing
- Payroll consolidation depends on → employee data validation → platform payroll system configuration → first pay run test
If you don't map these, you'll discover them the hard way-on the day something breaks.
Build Your Checklist, Then Go Execute It
The brutal reality: checklists don't win integrations. Execution does. But a well-structured, customised, actively managed checklist is the scaffolding that lets your team execute with confidence and speed.
That's the roadmap-from pre-close planning through Day 180 optimisation, across every workstream that matters. Now tailor it to your next deal: choose your integration level, assign owners, map dependencies, and track progress ruthlessly. Every acquisition is a test of whether you can turn a deal into operational reality before value starts leaking.
If your internal team is stretched thin-if IT is managing infrastructure and helpdesk for 200+ staff whilst trying to execute CRM migrations and data consolidation-you're not alone. At PMI Stack, we step in as the technical execution partner: we audit systems, map data, build the migration plan, and execute it whilst keeping the business running. We work with serial acquirers across facilities management, industrial services, healthcare, and home services, and we know where integration goes wrong and how to get it right.
If you'd like a second set of eyes on your integration roadmap-or you're facing a complex migration and need a partner who understands both the technical and operational side of M&A-get in touch. Happy to talk through your next acquisition and help you figure out what makes sense.
The checklist is the scaffolding. Execution is the building.
