M&A Due Diligence | Checklist & Overview

Jacob Orosz Portrait
by Jacob Orosz (President of Morgan & Westfield)

Executive Summary

After you accept an offer or letter of intent (LOI) on your business, the buyer will begin due diligence. Due diligence is the process of gathering and analyzing information to help the parties determine whether or not to proceed with a business transaction.

This period of time normally lasts 30 days but can be extended if both parties agree. In most circumstances, the buyer can walk away from the transaction if they are unsatisfied for any reason during due diligence.

So, what’s a seller to do? Start by conjuring up your best Boy Scout. Start by being prepared.

Doing proper due diligence on your own business will uncover any problems and give you a chance to resolve them before a buyer discovers them. We’ll show you how to do that in this article, in which we also answer the following questions:

  • What documents are typically given to the buyer before they make an offer?
  • What documents are usually given to the buyer after they make an offer (during due diligence)?
  • How should the seller manage buyers who request too much information before they make an offer?
  • How long does due diligence usually last?
  • What can the seller do to speed up due diligence?
  • What are reps and warranties, and how do they impact due diligence?
  • What is the typical due diligence process?
  • How should you prepare your business for due diligence?

Be sure to especially check out our sample due diligence checklist in the article below. It contains more than 70 items spread among seven broad categories. And you thought this would be the easy part.

What is the Purpose of Due Diligence?

Businesses are complicated — there are hundreds of factors buyers must take into consideration when deciding if they would like to move forward with the transaction.

When evaluating a home for sale, buyers can quickly form an opinion on the value and suitability of a home and hire an inspector to conduct a home inspection. Homes and other tangible purchases often require little to no due diligence. However, buying a business involves assessing many intangible factors that are not readily apparent and are more difficult to assess and evaluate.

As a result of this increased complexity, purchasers of businesses go through a lengthy and thorough due diligence process before completing the transaction.

This process does not begin until an offer is accepted by both parties.

With a business, the seller’s representations are verified during due diligence only after a letter of intent is mutually agreed upon. If all buyers conducted their due diligence before making an offer, sellers would spend a tremendous amount of time with many buyers and would risk a leak in confidentiality.

Conducting due diligence with multiple parties simultaneously may also lead the seller to lose focus on their business, and the value of the business may therefore decline. The buyer must accept the seller’s initial representations before an offer is accepted — only after an offer is accepted does the buyer have the opportunity to verify the seller’s representations.

Before accepting an offer, the seller should be cautious regarding what information is shown to a buyer. The seller should be helpful to the buyer, but they shouldn’t show them everything they ask to see. At some point, the seller should politely and tactfully ask the buyer to make an offer.

List of Documents and When They Are Shared

Here’s what to share BEFORE the offer is accepted:

Here’s what to share AFTER the offer is accepted (during due diligence):

  • Federal income tax returns
  • Bank statements
  • Invoices and receipts
  • Full copy of the lease
  • Leases, such as premise and equipment leases
  • Third-party contracts, such as supplier or vendor contracts
  • Sales and use tax reports
  • Staffing and payroll-related documents, including job descriptions and employment contracts
  • Insurance-related documents like workers’ compensation as well as health and liability insurance
  • Equipment inspection reports
  • Licenses and permits
  • Marketing, advertising, and promotional documents
  • Environmental documents and inspections
  • Franchise-related documents

The list above isn’t typical for every business. Each business will have its own unique due diligence structure. Most due diligence requests are more extensive than the list above.

Handling Buyers That Request Too Much Information

How do I handle a buyer who is requesting too much information (e.g., bank statements and tax returns) prior to submitting an offer?

Before receiving an offer, you should be cautious with what you show to buyers. You should certainly be helpful and engage with the buyers but do not give them everything they ask for. At some point, you should politely and tactfully ask them to present you with an offer.

Explain to the buyer that a thorough investigation can be conducted only after an offer is accepted. Tactfully point out that once an offer is accepted, the buyer will have plenty of time to perform their due diligence and verify the accuracy of your representations.

Explain to the buyer that you are making representations and that these representations are verified during due diligence.

How Long is Due Diligence?

Due diligence can take any period of time as long as both you and the buyer agree. The typical due diligence period for most small to mid-sized businesses is 30 to 60 days.

The length of due diligence should be based on the following:

  • Availability of information. If the seller responds promptly to the buyer’s document requests, the due diligence period can be shorter.
  • Turnaround time. This depends on how fast the buyer reviews the information. If the seller provides information that’s concise, organized, and clear, you’ll speed up the due diligence period.
  • Communication. If the seller is more available to the buyer, this may also shorten the due diligence period.

The Importance of ‘Representations’ and ‘Warranties’

Due diligence is never perfect — it can never uncover every potential problem with a business. You can never be absolutely assured that the business is without problems. In fact, there is no such thing as a “perfect” business.

If due diligence doesn’t ensure that the business is problem-free, what can be done?

“Representations” and “warranties” are statements and guarantees by the seller of a business relating to the assets, liabilities, and other elements of the business being sold. In the purchase agreement, the seller will have to make factual statements regarding the condition of the business, covering nearly all aspects of the company. These are referred to as “‘reps and warranties.”

Essentially, the seller is assuring the buyer that their representations are true, and if proven to be otherwise, the buyer is entitled to seek legal remedies, which could result in the seller reimbursing the buyer for damages. The representations and warranties collectively serve to mitigate the risk of any material defects that were not discovered during due diligence.

  • A representation is a statement of fact. If a representation is untrue, it is “inaccurate.”

For example, a seller may represent that the assets of the business are in good repair, that all inventory is salable, that there are no hazardous substances used in the business, that the business has operated in compliance with all laws, or that the seller has the legal capacity to sign the purchase agreement.

  • A warranty is an assurance. If a warranty is untrue, it is “breached.”

For example, a seller may warrant that they will operate the business in a regular and normal manner and will comply with all laws until closing, or that they will pay all payroll taxes that will come due from past operations up to the time of closing.

  • Representations and warranties in the purchase agreement assure the buyer that legal remedies may be available if the seller fails to disclose any material facts regarding the business that aren’t discovered during due diligence. This assures the buyer that additional protection is available if the seller is not fully forthcoming during due diligence.

The Process

Here’s a summary of how due diligence fits into the sale process:

Letter of Intent

The parties negotiate and accept the letter of intent.

Due Diligence

The due diligence period begins immediately after the letter of intent is accepted by the parties.

Purchase Agreement

The parties normally begin preparing a draft of the purchase agreement during due diligence. The purchase agreement often takes several weeks to negotiate and finalize, so the process usually starts during due diligence to ensure an efficient closing with minimal delays.

Conclusion of Due Diligence

At any point during due diligence or upon its expiration, the buyer may decide they are satisfied with their investigation of the business and will proceed with the transaction. The buyer may do this because the buyer and the seller have resolved the contingencies, or even if there are pending contingencies, the buyer may feel confident enough to enter into a definitive agreement.

When this happens, the buyer and seller will sign an agreement stating that due diligence has concluded. This signifies the completion of due diligence and the parties’ decision to end the investigation and proceed to a definitive agreement.

Additional Deposit, If Applicable

For smaller transactions, the buyer will place an additional deposit with the escrow company upon signing off on the completion of due diligence. If the transaction is canceled due to the buyer’s fault before a definitive agreement is signed, the buyer will forfeit both the initial and additional deposits. Otherwise, these deposits will be applied to the final purchase price.

Contingencies that Survive Due Diligence

There are often contingencies that survive due diligence, such as bank financing, franchisor approval, lease assignment, or license transfers. These remain as contingencies and are resolved between the conclusion of due diligence and the closing. The buyer may cancel the transaction if these contingencies are not met.


Once the contingencies are met, the closing may occur. In most cases, the purchase agreement is signed at closing. However, it may sometimes be signed prior to closing.

Due-Diligence Checklist

Here is a sample due diligence checklist:


  • Advertising contracts
  • Customer list
  • Inventory count
  • List of key competitors
  • Marketing material
  • Operations manual
  • Preliminary equipment inspection
  • Premises lease
  • Summary of key lease terms
  • Supplier and vendor list
  • Supplier/vendor contracts


  • Health insurance policies
  • Liability insurance policies
  • Workers’ compensation policies and history

Related Resource


  • Description of any real estate owned
  • Equipment inspection
  • Equipment leases
  • Equipment list
  • List of all assets included in price
  • Inventory list


  • Accounts payable schedule
  • Accounts receivable aging schedule
  • Annual personal property tax certificate
  • Backup data of adjustments to financials
  • Bank statements
  • Breakdown of sales by customer
  • Breakdown of sales by product type
  • Copies of existing loan or financing agreements
  • Customer or client agreements
  • Documentation for add-backs to financial statements
  • Federal income tax returns
  • Financial budgets and projections
  • Full QuickBooks or accounting software file
  • General ledger or detailed list of all transactions and expenses
  • List of monthly sales since inception
  • Merchant account statements
  • Payroll tax reports
  • Profit & loss statements
  • Sales and use tax reports
  • Utility bills

Related Resource


  • Benefit plans
  • Compensation arrangements
  • Detailed schedule of payroll expenses
  • Employment, agency, and independent contractor agreements
  • Job descriptions
  • List of outside contractors
  • Other employment-related agreements
  • Overview of personnel turnover
  • Schedule of owners, officers, employees, independent contractors, consultants, and their titles, length of service, and compensation benefits
  • Summary biographies of key management


  • Articles of incorporation/organization
  • Business license
  • Certificate of status/good standing from Secretary of State
  • Copies of licenses, permits, certificates, registrations, and other from all governmental authorities
  • Copy of all key contracts
  • Corporate/LLC by-laws or operating agreements
  • Corporate/LLC minutes
  • Description of environmental liabilities
  • Fictitious business name statement (DBA)
  • Financing agreements
  • Information for copyrights
  • Information for patents
  • Information for trademarks and service marks
  • List of liens against the business
  • Other third-party agreements or contracts
  • Pending lawsuits
  • Phase 1 and 2 environmental studies
  • Preliminary UCC search results
  • Previous purchase agreement and related documents for business
  • Resale permit
  • Seller’s disclosure statement

Tips for Conducting Due Diligence

Be Emotionally Prepared. Due diligence can be a grueling time for the seller. You must be prepared to commit a substantial amount of time and energy to the process. Some buyers’ objective is to wear you down, discover problems, and then attempt to renegotiate the terms of the deal. Be prepared for this possibility by preparing for due diligence so problems are uncovered and resolved before a buyer discovers them. You should also attempt to remain emotionally unattached to the process so you can negotiate from a detached, objective perspective.

Buyer Type Determines Thoroughness. Individuals are generally less thorough than companies in conducting due diligence. However, some individuals can be especially thorough if they are detail-oriented, are very risk-averse, or have a CPA or attorney advising behind the scenes. Most companies are thorough, especially if they have completed multiple acquisitions in the past.

Exclusivity. Keep your business on the market even once you’ve received an offer unless you have negotiated an exclusivity period with the buyer.

Don’t lose your focus. You must be prepared to spend significant time and energy during the due diligence process. By the time you reach the due diligence stage, you may feel as if you are almost done, but this is a critical stage where the sale can be made or lost. If you lose focus at this point, the deal can die. You are only on the fifty-yard line at this point. There is still a lot of work to be done before the sale is complete. It’s important that you stay engaged and actively involved in due diligence in order to reach your ultimate goal of a smooth closing.

Involve Your Accountant. Since much of the documentation needed for due diligence is financial in nature, you should consider including your accountant or CFO in your plans as early as possible to help prepare for due diligence. The more cooperation you have from your team, the smoother the process will go.

Designate a Point Man. The point man should be the quarterback during the transaction and should orchestrate the communication with all parties involved and review all information before it is released to the buyer. Many professional advisors will lose you as a client if the transaction is successful and they may not be inclined to conclude the transaction as quickly as possible due to their hourly-rate fee structure. Being the point man yourself or appointing someone within the company will help simplify the due diligence process.

Contact the Landlord Early. The lease is one of the most critical elements of the process and needs to be carefully orchestrated. Issues around the transfer of a lease are common, so the process must be handled with care. Landlords are not required to approve the lease transfer, and delaying the landlord’s involvement can create issues that delay the closing or prevent it altogether. We recommend involving the landlord as early as possible in the process.

Prequalify the buyer. Be sure that you have pre-qualified the buyer before negotiating and accepting an offer. You want to be sure that you are negotiating with a buyer who has the financial capacity to close the transaction.

Tell the Buyer You are Prepared. If you’ve prepared your business for sale and organized all the documents, be sure to mention the same in early conversations with buyers. You could say something like this:

“I’m a motivated, serious seller who has prepared my business for sale with the help of a certified public accountant (CPA). I have all the necessary documents ready for due diligence, including tax returns, leases, equipment lists, financial statements, and more.”

Why Should I Prepare for Due Diligence?

Can’t I just prepare the documents when the buyer requests them?

Preparing your business for sale greatly increases your chances of success. Laying the groundwork for due diligence helps convince the buyer to agree to a shorter due-diligence period and decreases their perception of risk in your business.

By organizing the documents so they are ready for review, you’ll ensure the process is quick and simple. Immediately after you accept an offer, the buyer can start reviewing the documents. Time is your greatest enemy. Time can kill all deals. By preparing for due diligence, you potentially speed up the process and dramatically improve your chances of closing the deal.

You also increase the chances of receiving an offer. Many times, buyers are reluctant to make an offer on a business because they don’t want to risk the time and financial investment in performing due diligence only for there to be an undisclosed problem. Preparing for due diligence mitigates these concerns for buyers.

We highly recommend that you prepare for due diligence as early as possible. This is where your accountant or CFO can really help with gathering the documents you need.

In one recent transaction we worked on, due diligence was significantly delayed because the seller did not have copies of bank statements on hand and it took several weeks to obtain copies from the bank. This delay ended up resulting in a price concession because the economy took a dip during this time period.

You also demonstrate to the buyer that you’re serious when you take the time and effort to prepare your business for sale. Buyers prefer dealing with motivated, prepared sellers. Buyers are more likely to spend time with a seller whom they know has prepared for the sale.

How Should I Prepare for Due Diligence?

Preparing your business for due diligence is straightforward.

It involves assembling and organizing the documents that most buyers request and review during the due diligence period. You should then retain a third-party expert to review these documents and uncover any issues the buyer may discover during due diligence. You should then address any issues once they are uncovered.

The advantage to preparing for due diligence is that you will have the opportunity to resolve any issues on your own time, without the added stress of the transaction being dependent on its outcome. The need for having your financials prepared and organized as well as ensuring everything is ready from an operational and legal standpoint cannot be understated.

Preparing for financial due diligence is one of the most important parts of successfully closing the sale of your business. Because the number one deal-killer of business sales is incomplete or inaccurate financial records, this should prompt you to make it a priority to ensure that your financials are in order. Otherwise, you risk losing the buyer since financial inaccuracies will likely be discovered during due diligence.

No one wants to invest enormous amounts of time with a buyer only to lose them due to something that could have been prevented. Pre-sale financial due diligence should be conducted by a third party, preferably a CPA. Ideally, this should be conducted at least three to six months prior to beginning the sale process. This will give you ample time to resolve any issues that are uncovered during the process.


We strongly recommend that you invest time preparing your business for due diligence. Most business owners skip this step altogether. By preparing for this process, you will greatly improve the chances of a successful sale. Additionally, demonstrating to the buyer that you have prepared for due diligence increases the buyer’s confidence in your business and reduces their perception of fear.

Due diligence can be heaven or hell. If you have your financials in order, and all is well from an operational and legal standpoint, chances are due diligence will be uneventful and your business deal will take flight and bring you one step closer to the closing of your dreams. If you are unprepared and the buyer finds things amiss during due diligence, you will find yourself on the horns of a dilemma. Being prepared can go a long way in facilitating the outcome you want.