The phrase "golden rule" comes up regularly in public debate around local-authority debt. The rule exists, it is precise, and it is significantly more restrictive than the golden rule sometimes invoked for the State. It fits in one sentence in the Code général des collectivités territoriales (CGCT), article L.1612-4:
"The local authority's budget is in real balance when the operating section and the investment section are each voted in balance, with revenues and expenditures honestly assessed, and when the transfer from operating-section revenues to the investment section, added to the investment section's own resources, provides sufficient resources to cover the principal repayment of loan annuities falling due."
It is a technical text, but its consequences are simple and radical. This article explains what it forbids, what it allows, why it exists, and how Paris stands in relation to it today.
Three concrete prohibitions
Read in reverse, the sentence sets out three clear prohibitions:
1. No voted deficit
The operating section and the investment section must both be voted in balance. You cannot vote a primary budget that plans, from the outset, more expenditure than revenue. A deficit can only be observed after the fact — at execution, in the administrative account, if expected revenue did not come in or if expenditure overran.
2. No borrowing for day-to-day spending
A municipality cannot borrow to finance its operating expenditure. Staff salaries, electricity bills, fuel for refuse trucks, grants paid to associations, reimbursements to Restaurants Émeraude — all of this must be financed by current revenue (local taxes, State endowments, fees). Borrowing is strictly reserved for investment: construction, renovation, purchase of durable equipment.
3. No infinite debt rollover
The principal of the debt must be repaid from own resources — that is, from resources other than a new loan. You cannot indefinitely refinance principal by borrowing again. Concretely, the annual gross saving (operating revenue minus operating expenditure) must cover the annual principal repayment of the debt. If gross saving falls below the principal due, the municipality enters a trajectory that is not sustainable in the medium term.
Why this rule exists
The golden rule has an explicit objective: to protect the municipality's taxpayers and users from an intergenerational debt drift. The logic is simple: if a municipality borrows for its salaries, it is future residents — who will not have voted for the decision — who will pay, and they will have nothing to show for that loan in return.
By contrast, borrowing to build a school means making future generations bear part of the cost of a building they will actually use. This is the idea of the principle of intergenerational equivalence: those who pay the loan should be (roughly) those who benefit from it.
This rule has another, less often cited virtue: it forces budget transparency. When a municipality announces an increase in operating expenditure (recruitment, social services, opening of new facilities), it cannot hide the cost behind a loan — it must, in mirror, either increase current revenue or reduce other current expenditure. It is uncomfortable, but it is honest.
Concrete case: what the rule forbids
Imagine three municipal projects:
- Recruiting five sports educators to open a new municipal gym. Current expenditure (salaries + social contributions) → cannot be financed by borrowing. The municipality must find current revenue (property tax, fee increases on activities, reallocation) or give up.
- Building the gym itself. Investment → can be financed by borrowing, over the expected useful life of the facility (typically 25 to 50 years).
- Heavy renovation of an existing gym (roof works, accessibility upgrades). Investment → borrowing is possible. But routine maintenance (paint, plumbing, cleaning) remains current expenditure, financed from current revenue.
It is this boundary between investment and operating that structures the entire reading of a municipality's budget. The M57 accounting chart (used by Paris since 2019) materialises it in two distinct, sealed sections — except for the famous "transfer from the operating section to the investment section", which is precisely the mechanism through which gross saving is mobilised to finance part of annual investment.
How Paris is performing today
Across the six most recent executed fiscal years (Administrative Account), the City's gross saving — the first variable that the golden rule applies to — shows an uneven trajectory:
| Year | Operating revenue | Operating expenditure | Gross saving | Share of op. revenue |
|---|---|---|---|---|
| 2019 | €8.64Bn | €7.95Bn | €683M | 7.9% |
| 2020 | €8.29Bn | €8.25Bn | €46M | 0.6% |
| 2021 | €8.70Bn | €8.30Bn | €396M | 4.6% |
| 2022 | €9.21Bn | €8.71Bn | €506M | 5.5% |
| 2023 | €9.61Bn | €8.78Bn | €831M | 8.6% |
| 2024 | €9.67Bn | €9.38Bn | €297M | 3.1% |
The year 2020 illustrates the at-risk scenario: a collapse in revenue (massive losses in parking, transfer-tax revenue, public-service-delegation fees) combined with maintained spending (rigid payroll, emergency support) brings gross saving down to €46M — only 0.6% of current revenue. At this level, the golden rule is not broken (saving remains positive), but the room for manoeuvre to repay the principal of the debt becomes extremely narrow. It is mechanically this kind of situation that, if prolonged over several years, would push toward structural imbalance.
By contrast, 2023 shows an operating surplus of €831M (8.6%), above the comfort threshold generally retained by the regional audit chamber (~7%).
What happens if the rule breaks?
The CGCT provides a gradual prefectoral oversight mechanism, triggered by the regional audit chamber (CRC) if it finds that a budget is not voted in real balance or that the administrative account reveals a deficit incompatible with the golden rule. The mechanism goes through five stages — referral, public opinion, corrective plan, prefectoral substitution, imposed plan — and was detailed in our explanation of municipal bankruptcy. Almost all cases stop at stage 3: the municipality accepts a negotiated corrective plan, and the procedure closes.
Key takeaway: no French municipality of more than 10,000 residents has crossed the prefectoral substitution stage since 2015. The mechanism exists, it is dissuasive, but it is almost never applied — precisely because the CRCs intervene very early, at the first annual warning signals.
A rule that structures everything
The golden rule of article L.1612-4 is a short, almost procedural text. But it governs, in practice, the entire budget operation of a French municipality:
- It forces the accounting separation between operating and investment
- It imposes a positive current saving as a precondition for borrowing
- It limits debt to identifiable objects (one loan = one tangible investment)
- It protects the intergenerational equivalence of charges
- It ensures political transparency of annual trade-offs
It does not prevent difficulties. It does not guarantee the prudence of investment choices (a municipality can perfectly well borrow for an operation that will turn out to be disproportionate). But it imposes a minimum discipline, which largely explains why financial defaults of large French municipalities are rare — and why, when they occur, they almost exclusively concern very small towns that have committed to projects out of scale.
What these figures do not say
This analysis stops at what the open-public-data pipeline and the CGCT text allow us to say. It does not say:
- Whether the current golden rule is sufficient — some actors (Cour des comptes, OFGL) argue for additional indicators, notably on implicit debt (off-balance-sheet commitments, loan guarantees granted to third parties)
- Whether Paris should aim for higher gross saving — that is a legitimate political debate, depending on the desired investment trajectory and the level of public service maintained
- What the 2025-2027 trajectory will be — the votes of the Conseil de Paris program a forecast that actual execution may or may not confirm
What it does say, in one sentence: the golden rule is not a slogan, it is a precise text that forces every French municipality to separate what is financed by current taxes from what can be financed by spread-out borrowing. It is an old rule, modest in its phrasing, and decisive in its consequences.
Sources: Code général des collectivités territoriales, article L.1612-4 and related articles L.1612-1 to L.1612-20 (oversight mechanism) · open-public-data pipeline, file evolution_budget.json (operating revenue and expenditure by fiscal year 2019-2026, source dataset Open Data Paris "Comptes administratifs M57") · Annual reports of the Chambre régionale des comptes Île-de-France for the indicative gross-saving threshold. Figures in current euros, executed for 2019-2024, voted for 2025-2026.