From startup to scale-up: When do you need an in-house accountant?

In the early stages of a company, the tax advisor takes over the entire accounting. The company submits the missing receipts on a monthly basis, the tax advisor posts them, and queries are answered briefly. This works well as long as the volume is manageable.

Complexity increases with growth. More employees make expenses, incoming invoices need approval processes, and keeping track of missing receipts becomes a task in its own right. At some point, the question arises: do we need someone to take over bookkeeping internally? The answer today is different than it was a few years ago.

The boundary has shifted

A few years ago, the logic was simple. As soon as a company reached a certain size, an internal accountant was worthwhile because ongoing bookkeeping became too expensive or time-consuming to have done externally.

Today, it is significantly higher. The reason is the combination of modern software and a changed role of the tax advisor. What once was manual work now runs via interfaces and automated processes. Receipts are captured digitally and provided with booking suggestions, bank data flows in automatically, and credit card expenses are linked to receipts before they reach bookkeeping.

At the same time, how deeply a modern tax advisor intervenes in company processes has shifted. The limit from which you need an internal accountant has moved further back. In return, the limit from which a tax advisor supports systems and processes has moved forward. Both developments are interconnected.

The better the systems, the later the accountant

The most important lever lies in the quality of the systems and processes. The better equipped a company is with tools, the less manual work is required and the longer it can get by without an internal accountant.

A key example is expense management tools with integrated credit cards like Moss. Instead of employees making expenses and receipts being laboriously gathered later, the process runs in a structured way: every employee has a card with a defined budget and approval process, receipts are captured directly upon payment, OCR recognition reads the data, and expenses are assigned to the correct cost centers. The tax advisor accesses this data directly. What used to be the most common reason for internal accounting—keeping track of receipts as the number of employees grew—is thus largely solved.

The same applies to the other building blocks of the finance stack. Invoicing software that automatically transfers outgoing invoices to DATEV. Banks that connect via interface. HR systems that deliver payroll data in a structured way. If these systems are set up cleanly and connected to the tax advisory & accounting firm, the manual effort remains low, even as the company grows.

The role of the modern tax advisor

A modern tax advisor does not only help with accounting but also with setting up the systems and processes that make internal accounting superfluous for a long time. They advise on tool selection, set up the interfaces, and ensure that data flows without manual intermediate steps.

In addition, a modern tax advisor takes over tasks that were previously often the reason for an internal finance function. Ideally, they support with timely investor reporting, the adaptation of the profit and loss statement to the company's requirements, and the preparation of evaluations that go beyond the standard business analysis (BWA). Closing within a few days after the end of the month is standard, not an exception, with a clean setup.

This does not mean that the internal accountant becomes superfluous. It means that the point at which they become necessary occurs later and that cooperation with the tax advisor remains central even after that.

When an internal accountant becomes necessary

Despite all automation, there comes a point when an internal accountant becomes indispensable. This is less a question of pure company size and more a question of operational complexity.

The decisive trigger is when daily bookkeeping becomes relevant. As long as accounting works in monthly cycles, a well-positioned external setup is sufficient. But as soon as decisions have to be made daily that require up-to-date bookkeeping, you need someone in-house.

Specifically, this is shown by several developments. The number of employees who manage expenses increases sharply, and with it the number of approvals, queries, and special cases. Supplier relationships become more complex, with individual payment terms and conditions. The company needs a week-to-week view of its liquidity, not just a monthly one. Payments must be coordinated and executed at defined times, instead of individually and ad hoc.

When these points come together, external accounting is no longer sufficient because it cannot provide the daily cadence and operational proximity that the company then needs.

What an internal accountant specifically delivers

An internal accountant takes over tasks that go beyond ongoing bookkeeping and enable operational control.

Coordinated payment runs. Instead of paying invoices individually and ad hoc, an internal accountant organizes regular payment runs. Incoming invoices are checked, approved, and paid in bundles at fixed times. This creates clarity, makes optimal use of payment terms, and avoids both late payments and unnecessarily early outflows of liquidity.

Clear overview of accounts receivable and accounts payable. The accountant keeps track of outstanding receivables and liabilities. On the accounts receivable side, this means active receivables management: monitoring which customer invoices are outstanding, reminding of payments in good time, and assessing the risk of payment defaults. On the accounts payable side, it means keeping an eye on liabilities and servicing them on time.

Weekly liquidity planning. This is often the actual reason for internalisation. Together, accounts receivable and accounts payable data create a picture of when and how much money is flowing in and out. An internal accountant can keep this view updated weekly and thus provide the basis for liquidity decisions. For a growing company where liquidity is a scarce resource, this is a central function.

Operational proximity and fast response. An internal accountant is part of the team and can react immediately to questions, clarify special cases, and coordinate with other departments. This speed cannot be achieved with a purely external setup beyond a certain complexity.

Coordination with the tax advisor remains central

A common misunderstanding is that an internal accountant replaces the tax advisor. The opposite is the case. Even with your own accounting, coordination with the tax advisor is essential.

The internal accountant handles the day-to-day, operational work. The tax advisor remains responsible for the annual financial statement, tax returns, tax structuring, and professional safeguarding of complex matters. Both must work closely together: shared charts of accounts, coordinated booking logic, and clear interfaces during data transfer. If this coordination does not work, it leads to double work, inconsistencies, and errors that become apparent at the latest during the annual financial statement.

In practice, the role of the tax advisor evolves with internalisation. Instead of day-to-day bookkeeping, they take on advisory and safeguarding functions more strongly, from structural tax planning to CFO advisory. Operational accounting moves in-house, while the specialized depth remains external.

The right sequence

For a growing company, this results in a clear sequence. First, clean systems and processes are set up, ideally with the support of a modern tax advisor. This phase lasts significantly longer than many expect. Only when operational complexity, the daily cadence, and the requirements for liquidity control actually demand an internal accountant is internalisation carried out.

Anyone who adheres to this sequence avoids a common mistake: hiring an accountant too early, who then takes on tasks that could be automated or handled by the tax advisor with a clean setup. And those who wait too long risk having operational control suffer because external accounting cannot deliver the necessary cadence.

The key insight: The question is no longer just from which number of employees an accountant makes sense. The question is whether the systems and the tax advisor are set up in such a way that internal accounting only becomes necessary when real operational control requires it. If you are positioned correctly here, you not only save costs but also gain flexibility.