Day 1 Human Resources M&A Plan

Covers all HR activities leading up to and including close and Day 1/Week 1. Accompanying reports — Day 1 Checklist, RAID Log, Milestones, and Executive Dashboard — reflect progress as of T-0 (close day). The full plan is at 100-Day HR Post-Merger Integration Plan.

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Day 1 Human Resources M&A Plan
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Here are the 10 more important steps for HR in the plan, focused on Day 1 readiness and executing Day 1 / Week 1:

  1. Confirm payroll is ready to run — establish payroll funding accounts, prepare tax IDs and state registrations, and schedule the first pay cycle for acquired employees, since a missed or wrong first paycheck is the fastest way to lose trust.
  2. Set up and staff the HR integration inbox and hotline — tested and live before Day 1, so employees have a real place to bring questions and concerns.
  3. Create the employee-facing Day 1 FAQ and benefits summary card — covering benefits, payroll, reporting lines, coverage effective dates, and key contacts for the Employee Communication Guide.
  4. Determine the interim org structure — combined-entity reporting lines effective Day 1, so no acquired employee is unsure who they report to.
  5. Prepare all required Day 1 legal notices and any separation packages — WARN, ERISA, and benefit-change notifications, plus compliant separation packages for any roles being eliminated on Day 1.
  6. Clear the HR Day 1 Readiness Gate — the formal checkpoint confirming systems are tested, communications are ready, and no unresolved blockers remain.
  7. Brief HR managers on talking points and escalation protocols — so every manager can field employee questions consistently and knows where to route what they can't answer.
  8. Distribute the CEO and CHRO Day 1 welcome message — delivered to employees across both companies to set tone and reassure.
  9. Confirm system access and communicate any separations — verify email, collaboration tools, and HR systems work for all acquired staff, and deliver separation packages to anyone affected by Day 1 changes.
  10. Close out Week 1 with employee-facing touchpoints — launch the HR integration intranet page, begin the combined onboarding program, complete 401(k) enrollment communications, and hold an HR town hall at the end of Week 1.

These actions reflect HR's core Day 1 job: make sure people get paid, know who they report to, and have a clear place to turn with questions — the groundwork so the integration begins on steady footing.