Day one banking after an acquisition: the integration checklist

Deal teams spend months on price, structure and financing. Banking often gets a few lines in the integration plan, usually under finance or IT.

Then day one arrives. Payroll has to run, suppliers have to be paid, and the banks want documents nobody prepared.

Why does banking break on day one?

Banks act on documents, not on announcements. A change of ownership does not update a bank mandate, a signatory list or a payment approval rule by itself.

At the same time, the change of ownership triggers know your customer reviews at every bank. Banks need the new ownership structure, often including the fund and its beneficial owners.

Facilities and pooling agreements add a third risk. Change of control clauses can require consent, repayment or termination at close.

None of this is complicated. It simply has to start before close, because banks work to their own timelines.

What must be done before close?

The weeks between signing and close are the most valuable time in the whole integration. Use them for the items banks cannot rush.

• List every bank, account, signatory and banking portal user across all entities.
• Prepare board resolutions, updated mandates and specimen signatures for each bank.
• Submit KYC information on the new ownership structure, including beneficial owners.
• Review facilities, guarantees, hedging agreements and pooling contracts for change of control terms.
• Agree consents, repayments or replacements with lenders where those terms apply.
• Confirm which services the seller provides under a transition agreement, and for how long.

Each item needs a named owner. Without one, the work falls between legal, finance and the deal team.

What should the document pack for each bank contain?

Banks process changes faster when everything arrives at once. A single, complete pack per bank avoids weeks of back and forth.

• Board resolutions authorizing the new mandates and signatories.
• Specimen signatures and identification for every new signatory.
• The new ownership chart, down to the ultimate beneficial owners.
• Registry extracts and constitutional documents for each entity.
• A list of portal users to add and remove, with their approval limits.
• A named contact who can answer the bank's follow-up questions quickly.

Ask each bank for its own checklist early. Requirements differ, and a missing document can hold the whole file.

What must work on day one itself?

Day one is about continuity. The business should not notice that its owner has changed.

• Payroll runs from accounts the company can access and approve.
• Supplier payments go out under approval rules that reflect the new management.
• Customer collections keep arriving in accounts the company controls.
• Treasury can see cash balances across every bank, even if manually at first.
• Former signatories who left with the seller have lost their banking access.

If any of these fails, it fails in public. Suppliers and employees notice before the board does.

A short dry run in the week before close helps. Test one payment and one approval at each bank with the new users.

What happens in the first 30 days after close?

The first month stabilizes control and builds the baseline. KYC files are tracked bank by bank, and any open mandate changes are chased to completion.

Treasury builds a daily cash position across all accounts. The finance team collects statements, fee schedules and facility terms for the cost review that follows.

This is also when the target bank panel takes shape. The combined group rarely needs every bank both companies brought into the deal.

Worked example: an illustrative integration timeline

The table shows an illustrative timeline for a hypothetical acquisition. The timing is invented to show sequence and dependencies. It is not a standard, and real timing depends on the banks and countries involved.

The dependencies matter more than the dates. Mandates depend on board resolutions, and the exit from seller services depends on new accounts being live.

How do transition service agreements affect day one?

In a carve-out, the seller often keeps running bank accounts, payments and treasury services for a period. The buyer depends on the seller's systems and staff while new accounts are opened.

A transition agreement buys time, but it also creates risk. Payments run on another company's controls, and visibility depends on reports the seller provides.

The exit plan should list every service the seller provides and its replacement. Each replacement needs a date, an owner and a test before the switch.

What the bank sees

From the bank side, an acquisition is first a compliance event. The KYC team must understand the new owners before anything else can change.

Relationship managers see an opportunity at the same time. They know the combined group will review its bank panel, and they want to be on it.

Banks also see which clients arrive prepared. A complete document pack, a named contact and a clear timeline move a client up the queue.

Incomplete files sit in that queue. The delay is rarely deliberate, but it lands on the client's day one all the same.

How should banks be consolidated in the first 180 days?

Start with the target panel, built from the needs of the combined group. Credit, cash management coverage and countries decide which banks stay.

Then migrate accounts in an order that protects the business. Collections and payroll move last, once new accounts have run cleanly for a cycle.

Close old accounts only after balances, payments and direct debits have moved. Closing too early is the most common way to break a supplier payment.

Tell customers and suppliers about new account details well in advance. Some will keep paying into old accounts for months.

What are the most common day one failures?

Most failures come from timing and ownership, not from technical complexity. These are the ones to plan against.

• KYC started after close, so new mandates are not live on day one.
• Former signatories still active on accounts the seller no longer controls.
• A facility with a change of control clause discovered in the week of closing.
• Seller services under a transition agreement with no agreed exit date.
• Accounts closed before every payment and direct debit was moved.

Who should own day one banking?

One person should own the banking workstream from signing to day 180. That person needs authority across legal, finance and IT, and direct contact with each bank.

Independent post-acquisition treasury integration support takes on that role when the internal team is stretched. Many of the risks surface earlier in treasury due diligence.

After day one, the work continues into the 100 day banking review. Day one is about control, and the 100 days are about cost and structure.

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This insight reflects general analysis and observations from FIRMA Advisory's work in treasury, banking, and cross-border financial advisory. It does not constitute investment advice, financial advice, or a recommendation in respect of any specific security, transaction, or financial decision. For analysis specific to your organization, contact us at [email protected].