The short answer
External finance support is almost always sold as if finance leadership were the problem. In most cases it is not. The finance leader is there and knows what needs doing – what is missing is capacity for a peak load, or specialist knowledge for a task that comes up once every five years.
That does not call for an interim CFO. It calls for a bounded module that works for the CFO and respects their priorities and approvals.
Four modules, each engaged on its own
Interim accounting. When documents pile up, accounts are unreconciled or parental leave has to be bridged. The brief is bounded by entity, period and account range; running bookkeeping and backlog clearance stay separate so that no new backlog builds. How to locate the bottleneck is in closing backlog and fast close.
FP&A and financial modelling. When the closing data is there but the forecast, the scenarios or a model for a funding round is missing. That is project work with a clear end, not a permanent position.
Special tasks with an expiry date. Consolidation across several entities, an IFRS conversion, a system change, a carve-out balance sheet, the data basis for a due diligence. Tasks for which nobody creates a permanent role.
Sparring without line responsibility. A counterpart for bank meetings, shareholder rounds or a valuation question – a few days a month, without anyone intervening in the organisation.
The role question, answered honestly
The real objection is rarely spoken but always present: what does the shareholder think when the CFO brings in external help? And does the external person end up taking the role?
Both can be answered contractually, before the start:
- The brief describes a result, not a role. "Account reconciliation for three entities by the end of Q3, reviewed and signed off" is something different from "support in the finance area".
- Priorities and approvals stay with the CFO. Whoever steers the input also decides what comes first.
- The reporting line is named. If the external person reports directly to the shareholder, that is a different construction – and it should then be called that.
In practice a bounded reinforcement strengthens the CFO's position rather than weakening it: the backlog is gone, the forecast is there, and the discussion about the reliability of the numbers stops.
When it does take the leadership role
Three situations argue against the module and for filling the leadership seat:
- Nobody is missing for the work, but someone is missing to decide and approve.
- The brief requires leading a team – prioritisation, conflicts, hiring.
- External communication has to be taken over, towards the bank, the fund or the auditor.
The difference is set out in CFO handover and vacancy.
What a good brief contains
- Entity, period, account range or module – as narrow as possible.
- What exists at the end, and who reviews it.
- Who supplies input: data, access, subject-matter contacts.
- A date for an interim review, not only for the end.
- How the handover works when the module ends.
The full version, including how to compare proposals, is in briefing a mandate and comparing proposals.
A note for readers outside Germany
In a German subsidiary of an international group the modules map onto a familiar pattern: statutory accounts under HGB and the tax-advisor handover are the recurring peak loads, and the consolidation onto group reporting is the special task that has no permanent owner. Both fit the bounded-module model better than a leadership placement – provided the German managing director keeps the approvals.
Frequently asked questions
Does the external person end up taking my role?
Not if the brief describes a result and priorities and approvals stay with the CFO. Both belong in writing before the start – then the question is settled rather than open.
How small can a brief be?
A bounded module is enough: one account range, one model, one consolidation. One day a week is a normal scope when the task is clear.
What does it cost compared with a permanent position?
For a peak load almost always less, because no permanent capacity is created. For steady demand the calculation tips. The ranges are on the pricing page.
What does the shareholder say?
In PE- and VC-backed companies a fixed-term reinforcement is a normal instrument. What lands badly is not the external help but the late close it would have prevented.
Can it become an ongoing arrangement?
Yes, as CFO as a service with a monthly retainer for running tasks. The difference to the fixed-term module lies in predictability and scope, not in the division of roles.
Read on
- Accounting as a service · FP&A and financial modelling – the two most common modules.
- CFO as a service: modules and pricing models.
- Interim CFO, CFO as a service or permanent hire.
- Pricing · References.
Sources and status
The article is based on nugrow's mandate practice. Status: September 2026.