Capex: definition, calculation and challenges for your SME
Investments, budget, depreciation and cash: how to read the capex of an SME without reducing it to a simple expense.
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Outsourced CFO in France | Fractional finance leaderExpert note: This article was written by our chartered accountancy firm. Information is current as of 2026. For a personalised review of your situation, contact us.
Updated March 2026 - capex (abbreviation of capital expenditure) designates the investment expenditures that a company undertakes to acquire, create or sustainably improve a fixed asset. For an SME, capex management is a strategic subject: it directly links management's vision, available cash, future depreciation and the financing plan.
Too many executives treat their investments as simple one-off cash outflows. However, each euro committed to a capex must be evaluated in terms of its complete life cycle, its financing method and its expected economic return. An SME that invests poorly, or at the wrong time, can find itself in cash flow constraints even if its business is otherwise healthy.
What is capex and how to calculate it?#
Capex represents all cash flows devoted to the acquisition or rehabilitation of fixed assets. Concretely, it covers expenses incurred for goods that will be used in the activity for more than one accounting year.
The capex calculation formula#
The most reliable method consists of using fixed assets recorded on the balance sheet:
Capex = Net fixed assets at the end of the period - Net fixed assets at the beginning of the period + Depreciation allowance for the period
This formula makes it possible to reconstitute the gross investments made, independently of the effect of accounting depreciation. It is found in the analysis of cash flow tables (IAS 7 flow table or French présentation).
Capex versus opex: the border to know#
The distinction between capex (investment) and opex (operating expenses) is fundamental. Rent, routine maintenance or a SaaS software subscription fall under the opex: these are expenses déductible immediately from the result. Conversely, the purchase of industrial equipment, the construction of a warehouse or the development of immobilizable internal software constitute capex.
This border is not just an accounting issue. It has a direct impact on the taxable income, on the présentation of the balance sheet and on the negotiation with financiers.
What to include in the capex of an SME#
The scope of investment expenditures varies depending on the nature of the activity, but we generally find the following catégories:
- Materials and equipment: machines, tools, professional vehicles;
- Production tools: manufacturing lines, specialized equipment;
- Immobilizable software: purchased software packages, internal developments meeting the immobilization criteria of the General Accounting Plan;
- Works and constructions: buildings, extensions, major works;
- Arrangements and fittings: premises installations, air conditioning, networks;
- Intangible assets: patents, licenses, goodwill depending on their nature and useful life.
The General Accounting Plan (PCG) sets the rules for immobilization. In practice, the question often arises for hybrid expenses: is a software upgrade a charge or an investment? The answer depends on whether the expenditure increases productive capacity or extends the useful life of the asset.
Why capex never reads alone#
An isolated amount of capex means nothing. For it to become a true steering indicator, it must be put into perspective with several complementary dimensions.
The link with depreciation#
Each investment generates depreciation charges which affect the accounting results over several years. High capex today means recurring future charges. The company must ensure that its future margin will absorb these allocations without jeopardizing its profitability.
The impact on cash flow#
The investment is paid in cash or in installments, while depreciation is a non-cash charge. This asymmetry is at the heart of many cash flow tensions in SMEs. A company can be profitable in accounting terms and yet be suffocated by the weight of its investment disbursements.
The financing method#
The choice between self-financing, bank loan, leasing or investment grant modifiés the financial structure and the risk profile. An investment financed 100% with equity does not have the same impact as a high investment, even if the acquired asset is identical.
The expected economic return#
All capex must be linked to a measurable objective: productivity gain, capacity increase, cost reduction, regulatory compliance, or opening of a new market. Without this anchor, investment becomes indiscriminate spending.
Hayot Expertise Advice: a profitable capex in the long term can remain poorly calibrated if its disbursement schedule weakens cash flow in the short term. Never separate economic analysis from cash flow analysis.
Common mistakes made by SMEs when it comes to investment#
**Field experience shows that certain errors recur systematically:
- Investing without a financing plan: the company signs a purchase order without having verified the sustainability of the deadlines;
- Underestimate additional costs: installation, training, maintenance, insurance, compliance;
- Confusing urgency with priority: replacing broken down equipment urgently without comparing alternatives;
- Neglect the tax dimension: certain catégories of investment give rise to exceptional depreciation, tax credits or public aid;
- Forget the exit cost: what happens if the equipment must be replaced or resold before the end of its useful life?
How to structure a relevant investment budget#
1. Qualify the need#
First of all figures, it is necessary to categorize the investment:
- Replacement investment: maintain the existing level of activity;
- Productivity investment: reduce costs or improve quality;
- Capacity investment: respond to anticipated growth;
- Strategic investment: penetration of a new market, innovation, digital transformation.
Each category calls for a différent level of analysis and validation. A strategic investment of 200,000 euros deserves more in-depth study than a replacement of equipment of 5,000 euros.
2. Calculate the total cost of ownership#
The purchase price is only part of the cost. It is necessary to add:
- installation and commissioning costs;
- team training;
- maintenance costs over the lifespan;
- consumables and spare parts;
- possible decommissioning costs.
3. Choose the right financing#
Funding must be calibrated to the economic useful life of the property. The Banque de France recalls in its financing référence that the adequacy between the duration of the resource and the duration of employment is a fundamental principle of sound financial management.
- Self-financing: ideal for small amounts, preserves financial independence;
- Bank loan: suitable for structuring material investments, with a leverage effect on the profitability of equity;
- Lease credit: flexible, allows you to maintain debt capacity, but the total cost is generally higher than the purchase;
- Subsidies and aid: not to be neglected, particularly in the context of the energy transition or digitalization.
4. Integrate capex into current management#
Once the investment is made, it must not disappear from the radar. Monitoring should include:
- the budget vs. actual comparison;
- monitoring depreciation and their impact on the result;
- performance indicators linked to the investment (productivity, availability rate, unit cost);
- a posteriori analysis: did the investment deliver the promised return?
Capex and taxation: the levers to know#
Taxation offers several mechanisms that can significantly modify the real cost of an investment:
- Dégressive depreciation: possible for certain industrial equipment and research materials, it allows the first years to be depreciated more quickly;
- Exceptional depreciation: put in place occasionally by the legislator to support certain types of investment (energy, digital transition);
- Excess depreciation: temporary device which allows an additional fraction of the acquisition cost to be deducted;
- Tax credits: research (CIR), energy transition, digitalization of SMEs.
These devices evolve regularly. An accountant is best placed to identify opportunities applicable to your situation and integrate them into your investment plan.
Conclusion#
In 2026, properly managing the capex of an SME means linking investment, operations and cash flow in an integrated vision. Good arbitration is not only accounting: it is economic, financial and strategic. Each euro invested must be justified by a measurable return, financed in a sustainable manner and monitored with the same rigor as turnover.
Companies that treat their investment budget as a real management tool — and not as a simple list of expenses — are those that sustainably build their compétitive advantage.
Frequently asked questions
Quelle est la différence entre capex et opex ?
Le capex (capital expenditure) correspond aux dépenses d'investissement qui creent ou augmentent la valeur d'un actif immobilise. Ces dépenses sont inscrites au bilan et amorties sur la durée d'utilisation du bien. L'opex (operational expenditure) désigne les charges courantes d'exploitation : loyers, salaires, fournitures, abonnements. L'opex est deduit immediatement du résultat, tandis que le capex l'est progressivement via les amortissements. Cette distinction a un impact direct sur la fiscalité, le bilan et la trésorerie de l'entreprise.
Comment calculer le capex a partir des états financiers ?
La formule la plus fiable est : Capex = Immobilisations nettes de fin de période - Immobilisations nettes de debut de période + Dotation aux amortissements de la période. On peut egalement le lire directement dans le tableau de flux de trésorerie, a la rubrique « Flux de trésorerie lies aux opérations d'investissement ». Pour une PME qui ne publie pas de tableau de flux, il suffit de comparer les postes d'immobilisations brutes entre deux bilans successifs.
Un logiciel est-il un capex ou un opex ?
Cela depend de la nature de la dépense. L'achat d'une licence logicielle permanente ou le développement d'un logiciel interne repondant aux critères du PCG constitue un capex immobilisable. En revanche, un abonnement SaaS (logiciel en mode cloud) est une charge d'exploitation (opex) car l'entreprise ne possede pas l'actif. La frontiere est importante : elle determine le traitement comptable, fiscal et l'impact sur le résultat.
Quel ratio utiliser pour évaluer l'efficacité des investissements ?
Plusieurs indicateurs sont pertinents selon le contexte : le ROI (retour sur investissement) mesure le gain net rapporte au coût investi ; la VAN (valeur actuelle nette) evalue la création de valeur en actualisant les flux futurs ; le délai de récupération (payback period) indique en combien de temps l'investissement est rembourse. Pour un pilotage courant, le ratio capex / chiffre d'affaires permet de situer l'effort d'investissement par rapport a la taille de l'entreprise et de le comparer aux standards du secteur.
Peut-on reduire le capex sans penaliser la croissance ?
Oui, en optimisant l'utilisation des actifs existants avant d'en acquerir de nouveaux. Le leasing operationnel, la mutualisation d'équipements, ou encore le recours a des prestations externalisees (opex) peuvent limiter les investissements lourds. L'important est de raisonner en coût complet et en flexibilité stratégique : un capex reduit artificiellement peut se traduire par une perte de compétitivité a moyen terme.

Article written by Samuel HAYOT
Chartered Accountant, registered with the Institute of Chartered Accountants.
Regulated French accounting and audit firm based in Paris 8, built to support companies across France with a digital and decision-oriented approach.
Sources
Official and operational sources cited for this page.
This topic is part of our service Outsourced CFO in France | Fractional finance leader
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