HR Due Diligence Checklist Template: 30 Items to Review Before You Sign an Acquisition

An HR due diligence checklist template is a structured list of the workforce, compensation, benefits, compliance and culture items a buyer reviews before signing an acquisition, with each item tied to a document request, an owner and a risk rating. Used properly, it turns people risk into numbers you can put in the purchase price, the indemnity schedule and the Day 1 integration plan. The 30 items below are the ones I would not sign without.

Why an HR Due Diligence Checklist Template Belongs in Every Deal

Financial diligence gets the partners and the data room gets the lawyers. HR diligence often gets a junior associate and a two-page questionnaire, which is a mistake, because people liabilities are where unpriced risk tends to hide. Mercer's M&A Readiness research surveyed more than 1,400 M&A professionals across 54 countries and found that 43% of transactions ran into culture issues serious enough to delay or terminate the deal or cut the purchase price. Mercer also found that 67% saw the expected gains from combining the two firms arrive late because of culture problems and 30% never met their financial targets because of them.

The hard-dollar cases are just as instructive. After Elon Musk's 2022 takeover of Twitter, about 6,000 laid-off employees sued, claiming at least $500 million in severance. Their argument rested on Twitter's 2019 severance plan, which they said promised most staff two months of base pay plus one week per year of service, and six months of base pay for senior staff. A federal judge dismissed the case in July 2024. The plaintiffs appealed with support from the US Department of Labor, and X Corp. reached a tentative class-wide settlement in August 2025, a month before the Ninth Circuit hearing, according to Bloomberg Law and TechCrunch. That fight began with a plan document that sat in the target's files before close.

Worker classification is the other classic trap. FedEx paid $240 million in 2016 to settle claims from drivers in 20 states who said they were misclassified as independent contractors. That came on top of a $228 million settlement in California and Oregon, for a combined $466 million and nearly 12 years of litigation. Any acquirer of FedEx Ground in those years would have inherited that tail.

Takeaway. Before kickoff, pull every severance plan, contractor agreement and change-of-control clause into one tracker. These three document types account for most of the surprises that turn up after close.

The 30-Item HR Due Diligence Checklist, Part 1: Workforce, Pay and Contracts

Each item below should have its own row in your Excel template with five columns: document requested, date received, reviewer, finding and risk rating (red, amber, green). Items 1 to 15 cover the structural facts of the workforce.

Workforce census and organization

Employee census. Name or ID, title, location, hire date, FLSA status, base pay, bonus target and manager. Reconcile headcount to payroll registers and the P&L.
Org chart to two levels below the CEO. Flag single points of failure.
Contractor and consultant roster. Tenure, hours, exclusivity and how they are managed. Long-tenured, full-time contractors are your FedEx risk.
Exempt vs. non-exempt classification. Test a sample of exempt roles against the duties tests, since overtime back pay compounds by year.
Headcount by jurisdiction. Each state and country brings its own leave, notice and termination rules.
Turnover and open requisitions for 24 months. Split voluntary from involuntary, and regretted from non-regretted.

Compensation and contracts

Executive employment agreements. Term, notice, good reason definitions and garden leave.
Change-of-control and severance provisions. Single vs. double trigger, plus multiples of salary.
All severance plans and policies, written or practiced. Twitter's 2019 plan is the reason this item stands alone.
Bonus and commission plans. Accrued but unpaid amounts, plan year timing and clawback terms.
Equity plan documents and cap table. Vesting acceleration, treatment of unvested awards and 409A valuations.
Retention or transaction bonuses already promised. Get them in writing from the seller, including verbal commitments.
Restrictive covenants. Non-competes, non-solicits and IP assignment, checked against enforceability in each state.
Offer letter template and any outliers. Look for guaranteed bonuses and side letters.
Pay equity snapshot. Base pay by gender and level for the largest job families.

Takeaway. Build the census first. Every later item (severance cost, WARN exposure, 280G testing) runs off that one spreadsheet, so a clean census cuts the rest of the review roughly in half.

The HR Due Diligence Checklist, Part 2: Benefits, Compliance, Liabilities and Culture

Items 16 to 30 are where contingent liabilities sit. They drive specific indemnities and escrow sizing.

Benefits and tax exposure

Benefit plan documents and summary plan descriptions. Health, retirement, life and disability.
Form 5500 filings for three years. Late or missing filings carry daily penalties.
Defined benefit and multiemployer pension exposure. Funded status and any withdrawal liability estimate.
Self-insured health claims and IBNR reserves. Make sure incurred-but-not-reported claims are accrued.
Section 280G analysis. Model parachute payments for every disqualified individual before signing.
Payroll tax filings and any open audits. Include state unemployment and international social charges.

Compliance and litigation

Pending and threatened employment claims. EEOC charges, wage-and-hour class actions, arbitration demands and settlements for five years.
Internal investigations and harassment complaints. Ask how many there were, who was investigated and how each closed.
I-9 and immigration status. Audit a sample of I-9s and list every visa holder who will need sponsorship transferred.
Union agreements and organizing activity. Collective bargaining agreements, successorship clauses and recent petitions.
Past layoffs and WARN compliance. Any layoffs in the past 90 days count toward aggregation.

Culture and retention

Key employee list. Roughly the top 5% of people whose departure would hurt revenue, product or customer relationships.
Engagement surveys and Glassdoor trends. Read the comments for patterns, since the scores alone tell you little.
Decision rights and operating cadence. Compare how each company approves spend, hires and ships product.
HR systems and data. HRIS, payroll provider, data privacy compliance and contract end dates.

Takeaway. Items 18, 20 and 22 are the ones most likely to justify a special indemnity or a dedicated escrow. Get counsel and an actuary on them in week one rather than week four.

How to Run HR Due Diligence Step by Step

A typical mid-market deal gives you three to six weeks of confirmatory diligence. This is the sequence I use.

Day 1 to 3, send the request list. Convert the 30 items into a numbered document request list that matches your data room index, and give the seller a due date for each section.
Week 1, build the census model. Load the employee census into a spreadsheet model and reconcile it to payroll. Investigate any gap above 2% before you go further.
Week 1 to 2, run the triage pass. Rate every item red, amber or green. Reds go to the deal team call that week.
Week 2, hold management interviews. Sit down with the CHRO or head of people, the CFO on payroll and benefits, and two or three line managers. Ask the managers who they would hate to lose.
Week 2 to 3, quantify. Put a dollar range on every red and amber item, such as severance cost under your planned restructuring, 280G excise exposure, misclassification back pay and pension underfunding.
Week 3 to 4, write the memo. Keep it to a two-page summary for the investment committee and attach the full tracker as an appendix.
Before signing, map findings to the SPA. Every quantified risk becomes a price adjustment, a specific indemnity, a closing condition or a covenant.

Plan WARN timing before you sign. Under the federal WARN Act, employers with 100 or more full-time employees must give 60 calendar days' written notice of a plant closing or mass layoff. In a sale, the seller owes notice for covered events up to and including the closing date, and the buyer owes it for events after closing. If your deal model assumes cost cuts in the first 60 days, the notice has to go out before close or the timeline slips. Several states, including New Jersey, run their own stricter mini-WARN rules on top of the federal law.

Takeaway. Put the WARN calendar and the 280G calculations on the same timeline as your signing and closing dates. Both depend on dates, and both cost the most when people find them late.

Turning Findings into Price, Indemnities and an Integration Plan

A finding only matters once it shows up in the deal documents or the integration budget. Here is how the most common ones translate.

Example: a 280G calculation

Section 280G applies when an executive's change-of-control payments equal or exceed three times their base amount, meaning average W-2 compensation over the prior five years. Once that threshold is crossed, the executive pays a 20% excise tax on everything above one times the base amount, and the company loses the deduction on that excess. Take an illustrative executive with a $400,000 base amount. The safe harbor is $1,199,999. A package of $1.25 million crosses the line, which puts $850,000 into excess parachute territory, about $170,000 of excise tax on the executive and a lost deduction for the company. Being $50,001 over the limit costs roughly $170,000 plus the tax effect. Private targets can often fix this with a shareholder cleansing vote, but only if someone runs the numbers before signing.

Mapping findings to deal terms

Known, quantifiable liabilities (accrued bonuses, unpaid PTO, underfunded pensions) go into the net working capital or debt-like items definition, so they come off the price dollar for dollar.
Contingent liabilities (misclassification claims, open EEOC charges) need a specific indemnity that sits outside the general basket, backed by escrow sized to your high-case estimate.
Key person risk calls for retention agreements signed at or before signing, often paid 50% at 12 months and 50% at 24 months, and sometimes a closing condition that a named set of people has signed.
Culture and systems gaps become lines in the 100-day integration plan with an owner and a budget.

Mercer's finding that 67% of deals saw culture slow the expected gains from combining is the case for budgeting integration costs during diligence rather than after close. If the target approves spend by consensus and your team approves it by delegation of authority, write the transition rule down before Day 1.

Takeaway. Add a final column to your tracker called "Deal treatment" and require every red or amber item to land in one of four places: price, indemnity, closing condition or integration plan. If an item lands nowhere, nobody has dealt with it.

Using an HR Due Diligence Checklist Template on Your Next Deal

The Twitter severance dispute and the FedEx settlements both came from documents and practices that existed before anyone signed. A disciplined HR due diligence checklist template catches those items early, puts a dollar figure on them and moves each one into the purchase agreement or the integration budget. Building the tracker, the request list, the census reconciliation, the 280G model and the WARN calendar from scratch takes a deal team days it does not have. A ready-made Excel template with all 30 items pre-loaded, risk scoring built in and a deal-treatment column already wired up lets you send the request list on day one and spend the remaining weeks on judgment instead of formatting. If you want the free download version or the full M&A diligence kit, start with the template and adjust it to the target's jurisdictions and headcount.