On the day of closing, little usually changes for the outside world. For the systems that process payments, a great deal may already have changed internally: banking relationships, signing authorities, entities. Payments that fail to go through are one of the few integration problems that become visible within a week to suppliers, employees and customers. That makes this component well suited to being mapped out sharply in advance, regardless of whether the rest of the organization has already been merged.
The first question is whether payroll administration remains on the old entity or transfers to a new structure. If nothing changes to the legal form or bank account, the risk is limited. If the legal entity, the bank, or the payroll provider changes, then before the first payroll run after closing it must be established who may approve the payment instruction, under what mandate, and from which account. That mandate is connected to the question of who decides what on Day 1 — salary payments are typically a decision that cannot wait for a broader integration plan.
Ongoing payment arrangements with suppliers are often recorded under the name of the old entity, with a specific account number and sometimes a specific contact person for approval. If the entity changes, it must be established whether suppliers will accept a new invoicing entity without interruption, and whether contracts specify anything about this. This directly touches on the question of which contracts require attention on Day 1 in a cross-border deal, because some supplier agreements contain a change-of-control clause that can affect payment or delivery.
Customers who pay by direct debit or who pay invoices to a fixed account number need to know where they stand — or, ideally, notice nothing at all. A change of IBAN, account name, or invoice address without notice leads to failed direct debits and delayed payments, which in turn causes unnecessary unrest among account managers. Whether and how this is communicated is connected to the broader question of what you communicate on Day 1: a change that is not explained is often misinterpreted.
Who may authorize a payment is often recorded per account and per amount. After closing, the formal governance may change while the bank still has the old signatories registered. That gap — between who is actually responsible and who the bank allows to sign — is one of the most common Day 1 problems with payments. It is connected to which legal-form steps have already been taken, something set out in which legal-form steps are needed on Day 1, and to which system access has already been transferred, see which access rights must be correct on Day 1.
If the organization pays internationally, extra layers come into play: local banking requirements, currency accounts, local VAT or payroll tax rules that differ per country. What needs to be arranged on Day 1 for a cross-border deal varies significantly by jurisdiction and is set out in detail at what needs to be arranged on Day 1 for a cross-border deal. A payment that is a routine action in one country may require separate approval or registration in another.
Not every payment process needs to be merged on Day 1. Merging payment systems, harmonizing payment terms, or consolidating banking relationships are decisions that often fit better in a Day 100 plan than in the first week. The question to ask at each of these steps is not only when something can be done, but whether merging at that moment adds value or mainly introduces risk. Two separate payment processes that function well are sometimes a better outcome than a hasty merger that introduces errors.
The Day 1 generator sets out payments as a separate category with dependencies: which bank mandates need to be arranged first before a payment can go through, which contracts need to be checked first, and which communication needs to go out first before a debtor changes anything in their own system. The integration office tracks which of these steps have been completed and which are still open, so that on the day itself there is an overview instead of separate action items scattered across different minds.
Once it is established which payments must keep running on Day 1, a list of repeatable checks often emerges: checking account numbers, verifying mandates, matching invoices to the new entity. Much of that work is repetitive and error-prone when done manually under time pressure. The work scan from FTE TO AI calculates, per task, what portion of it can be taken over by AI, so that it becomes clear where people need to keep checking and where a system can do the first pass of the work.
If you are waiting for access to the generators and the integration office, you can sign up for the waiting list. The tool is under construction; what is described here is the structure that will be delivered, not a service that is already available on demand.
Vraag maar wat er op Day 1 moet staan, of wat integreren juist kapotmaakt.
Answers come from this site’s knowledge base. Not tailored advice, and not a scan of your company.