Capex: definition, calculation and challenges for your SME

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.

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 presentation).

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 deductible 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 presentation of the balance sheet and on the negotiation with financiers.

The scope of investment expenditures varies depending on the nature of the activity, but we generally find the following categories:

• 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.

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 modifies 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.

**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 categories 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?

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 different 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 reference 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?

Taxation offers several mechanisms that can significantly modify the real cost of an investment:

• Degressive 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.