The morning after close, a technician will ask whether he gets paid on Friday, and a customer will ask who to call when a truck does not show. If you cannot answer both before lunch, the deal has already started to leak. Nobody will tell you. They will just start looking elsewhere.
Day 1 is not the start of integration. It is the first test of whether your planning before close was real. The people who came with the business are watching to see what kind of owner you are. On day 1 your only job is to make sure nothing that worked yesterday stops working today.
This list covers the items that decide that. It is not the whole integration. For the full set of tasks, use the post-merger integration checklist. For the order of work after day 1, use the first 100 days integration plan.
The rule for day 1: protect before you improve
Do not change anything on day 1 that you are not forced to change. Payroll runs the way it ran. The phone is answered the way it was answered. Write your good ideas down and hold them until the business is stable.
The exceptions are what changes by law or contract at close: who can sign, who is insured, who owns the bank accounts. Those must change, and change cleanly.
Get the day 1 tab as a working spreadsheet
The free 100 day integration tracker (XLS) includes a day 1 tab with an owner, a deadline, and a status on every line below. Assign it before you close.
How to read the checklist
Every item has an owner, the one role accountable, and a live by mark: before close, open of business, end of day 1, or end of week 1. Owners are written as roles because titles vary. In a smaller company one person may hold three of them. That is fine. An item with no name next to it is a day 2 problem.
The checklist, by function
If cash stops moving, nothing else matters
- Open or confirm every operating account the business needs, with the right signers loaded.
- Confirm you can receive customer payments into an account you control: checks, ACH, card processing, lockbox.
- Confirm outgoing payments clear: payables run, card payments, and any automatic drafts to vendors.
- Confirm the lender's requirements are met: account control, covenants, and the first reporting dates.
The first paycheck is the first promise you keep
- Confirm the next payroll runs on schedule, on the same calendar, with the same pay rules. Test it before close if the system is changing.
- Confirm health and other benefits carry over without a gap in coverage. No employee should find out at a pharmacy counter.
- Confirm commission, bonus, and incentive plans are paid as written. The plan that keeps your top producers stays as it is.
- Confirm tax registrations, employer accounts, and workers compensation coverage are in place for the new owner.
Someone has to be able to sign, and everyone has to know who
- Document signing authority: who can sign contracts, approve credit, hire, and commit spend, and up to what amount.
- List the contracts with change-of-control or assignment clauses, and confirm which consents you have and which you are still waiting on.
- Collect any handshake deals the seller made, and decide on purpose whether to honor them.
The coverage that protects you is often tied to the old owner
- Bind property, liability, auto, and workers compensation coverage for the new owner effective at close. Confirm the certificates reach the customers who require them.
- Confirm contractor licenses, trade licenses, and permits transfer, or list the ones that do not and the date each is fixed.
Know who has what, and what nobody should touch yet
- List every system in use: accounting, dispatch, job costing, inventory, CRM, phone, email, and the spreadsheets people actually run the business from.
- Confirm administrator access for at least two people you trust, and change shared passwords held by people who are leaving.
- Confirm the phone system, email, and web forms work. A dead main number is the fastest way to lose a customer on day 1.
- Freeze system migrations. Do not move the business onto your platforms until the 100 day plan says it is safe.
The customer should notice nothing except better news
- Confirm the same people answer the phone, schedule the work, and show up. The same trucks, the same faces, the same invoice.
- Name an account owner for each of the top accounts, and confirm the relationship holder is staying.
- Leave pricing, credit terms, and service levels alone. A quiet change to any of them is a reason to start shopping.
A supplier who hears it late can put you on credit hold
- Confirm every critical supplier knows who the new owner is, where invoices go, and that payment terms hold.
- Confirm account credit and purchasing authority are in place, so the first order on day 1 is not refused.
- Do not move purchasing to your master agreement yet. First find out why the company you bought got the rate it got.
The communications cascade
Communications is where a good day 1 is made or lost. The order matters, because people who hear news about their own job from somebody else do not forgive it. Keep the gap between steps to hours.
- Leadership and the critical few, before the announcement. The president, with the seller present if the seller is staying. Cover what is changing, what is not, and what you need from them. Owner: president. Live by: before close.
- All employees, same day. One meeting, or one call, then the same message in writing. Say what you know, what you do not know yet, and when you will tell them more. This is the awareness step in ADKAR, and it only works if it is honest. Owner: president with HR lead. Live by: open of business.
- Customers, starting with the top accounts. A personal call from someone they know, then a short note to everyone else. Owner: sales leader. Live by: end of day 1.
- Vendors and partners. A short note with the new contact, payment details, and the reassurance that terms hold. Owner: finance lead. Live by: end of day 1.
- Lenders, insurers, and outside advisers. Confirm what was promised at the deal table and the first reporting dates. Owner: president. Live by: end of week 1.
Match the message to your operating model. If you decided to preserve and strengthen, say plainly that the team, the brand, and the way of working stay. If you decided to selectively integrate, name the two or three areas that will change, and say that nothing else will. If you decided to substantially consolidate, do not pretend otherwise. People can handle a hard message told straight, not one that leaks out in pieces.
Decide now who gets the call, and who decides
- Publish one escalation contact for each function, with a mobile number, for the first 30 days.
- Set a short daily call for the first week: what broke, what is at risk, what is decided. Fifteen minutes. Same time.
- Start the issue log on day 1. Record every problem with the owner and the date. One issue is never just one issue, and the log is how you see the pattern.
What day 1 does not need
Leave rebranding, compensation changes, system migrations, synergy targets, and management restructuring for later. Each feels urgent and each has broken a good business when done too early. Expect a dip in morale and output once the news lands. That is the valley of despair, and a clean day 1 keeps it shallow enough that the business is still standing when it climbs.
After day 1
By the end of week 1, every item above should be done or have a named owner and a date. Then the work turns to the people and the customers who hold the value you bought. Read employee retention after acquisition and customer retention after acquisition next. If you are reading this before you have signed, go back one step to integration before close and the seller transition, because most day 1 failures are set up there.
Assign it before you close
A day 1 list nobody owns is a wish list. The tracker puts a name, a deadline, and a status on every line, and carries it forward into the first 100 days.
Questions
What is a day 1 readiness checklist?
It is the list of things that must be true when a deal closes so the business keeps running: payroll, cash access, signing authority, insurance, systems access, customer service, and communications. Each item has an owner and a deadline.
When should we start preparing for day 1?
Before you sign the purchase agreement, ideally while diligence is still open. Insurance, banking, license transfers, and change-of-control consents take weeks. Treat the day 1 list as an output of diligence.
Who owns day 1 readiness?
The president or the deal lead owns the whole list, and each function owns its own items. One person should hold the master list and run the daily call. If everyone owns it, nobody does.
Should we change anything on day 1?
Only what the close forces: authority, banking, insurance, and ownership records. Leave pricing, pay plans, systems, branding, and organization alone until you understand the business. The first priority is that nothing that worked yesterday breaks today.