The French Cour des comptes' cooperative audit with Germany's Bundesrechnungshof into public support for quantum computing finds a young, academically strong sector that has grown quickly on the back of the 2021-2025 national quantum strategy (SNQ), but whose foundations remain precarious. Almost all of the EUR 1 billion committed to quantum computing under the SNQ comes from the time-limited France 2030 investment plan rather than a durable budget line, and France will soon have to choose between maintaining, increasing or redirecting that effort. The many funding channels involved - France 2030 grants and repayable advances, research-agency and public-investment-bank schemes, regional subsidies, EU calls for projects and tax credits - are not tracked in a single consolidated view, and the training pipeline depends on financing whose continuation past 2027 is not secured. Public money remains indispensable because private investment is scarce - only one specialised venture-capital fund in France finances quantum technologies - leaving promising start-ups exposed to takeover by better-funded foreign competitors just as the sector enters a consolidation phase. The Cour des comptes recommends shifting the funding mix toward repayable advances and public procurement, consolidating the tracking of all financing, securing the training offer, monitoring strategic-sector companies more closely, and building targeted European industrial partnerships by 2028. At the joint initiative of France's Cour des comptes and Germany's Bundesrechnungshof, the Cour examined French public financial support for quantum computing - the branch of quantum technology aimed at building a working quantum computer, covering hardware platforms, the software stack, and the enabling technologies (lasers, cryostats) a machine needs to function; quantum sensors, quantum communication and post-quantum cryptography were excluded from scope. The inquiry was opened by letter to the administrations concerned on 10 September 2025 and covered training and the research continuum (fundamental research, R&D, innovation) as well as the emerging industrial fabric. The Cour conducted around sixty interviews with public administrations, agencies and a representative sample of companies, visited quantum-computing infrastructure mainly in the Paris region, carried out joint site visits with the German audit team around Bonn and Munich, and sent questionnaires to public bodies and companies; because spending is dispersed across institutions managing their own funds, the Cour had to estimate some higher-education and research financing rather than fully consolidate it, and could not consolidate or estimate total private-sector financing, which is often commercially confidential. The 2021-2025 national quantum strategy (SNQ) committed EUR 1.8 billion in investment, of which EUR 1.5 billion in public funds and EUR 1 billion earmarked for quantum computing specifically; EUR 597 million had been committed by 31 December 2025 across 40 projects. The PROQCIMA public-procurement programme is a framework contract with five selected start-ups initially capped at EUR 500 million, targeting a fault-tolerant quantum computer of 128 logical qubits by 2032 (extended to 2,048 by 2035); the target was revised in May 2026 to 1,024 logical qubits by 2032. The QuanTEduFrance training programme received EUR 56.7 million; France 2030 funded 124 postdoctoral researchers and 255 doctoral theses on quantum computing between 2021 and 2025 (within the National Research Agency's scope), and 37 master's programmes (13 of them quantum-specific) enrolled 1,061 students in 2024-25 across 23 partner universities. On 21 May 2026 the US Congress voted a USD 2 billion support package for quantum computing targeting nine companies; the following day the French President announced a further EUR 1 billion for quantum technologies through France 2030, on top of the funds already committed. The SNQ (2021-2025) is steered by an inter-ministerial governance structure and coordinated by the Secretariat-General for Investment (SGPI), consistent with the fact that most of its funding comes from the France 2030 investment plan, whose budget programmes SGPI itself manages. Support instruments include a dedicated PEPR research programme (EUR 142 million, led by the CNRS, CEA and INRIA), specialised operators channelling grants, repayable advances and equity stakes to public research (the National Research Agency, ANR) and to companies (Bpifrance), and the PROQCIMA public-procurement competition (EUR 500 million) among five selected firms. Supplementary financing comes from regional subsidies, European Union project calls, and corporate tax incentives (the CIR research tax credit, the JEI young-innovative-company status and the CII innovation tax credit), though each represents a much smaller share of the total than France 2030 funding. The inquiry was run as a cooperative audit with Germany's Bundesrechnungshof; the draft report was deliberated by the Cour's third chamber on 20 May 2026 and approved by the Cour's report and programmes committee on 2 June 2026. Public support for the private sector still relies more on grants than on repayable advances, even though the Cour recommends shifting the balance toward advances and greater use of public procurement (PROQCIMA) so that firms are pushed to consolidate financially rather than remain dependent on subsidy; only one specialised French venture-capital fund exists to finance quantum technologies, so firms struggling to raise private capital to scale up have few domestic alternatives to public money. Financing for quantum computing is dispersed across many channels - France 2030 grants and advances, ANR and Bpifrance schemes outside France 2030, regional subsidies, EU project calls and tax credits - with no single consolidated view of the totals by origin and destination; the Cour itself could not fully collect or verify all higher-education and research spending within the time available and had to rely on estimates from the main institutions instead of a detailed consolidation. Despite a decade of sustained public investment, the domestic industrial ecosystem remains fragile and dependent on public funds, because the market for quantum computers is not yet large enough to make the sector profitable on its own; France has not yet made the explicit strategic choice - between maintaining, increasing or redirecting its funding, and between specialising, positioning itself as a hub, or accepting dependency on a dominant foreign partner - that its sovereignty objective requires as the sector enters a consolidation phase marked by predation risks from better-funded foreign competitors. The Cour recommends that, "in the support provided to the private sector, the weight of repayable advances relative to grants be increased, and greater use be made of public procurement through the PROQCIMA programme, in order to facilitate the consolidation of companies" (Recommendations, no.2, p.13). Firms' difficulty in raising private capital to scale up makes them vulnerable to being acquired by better-funded foreign actors, and only one specialised French venture-capital fund finances quantum technologies (Synthese, p.11). The Cour recommends reinforcing "the consolidated monitoring of all financing, which is cross-cutting by nature, both in its destination and in its origin" (Recommendations, no.3, p.13). Consolidating the totality of financing allocated to quantum computing was hampered by spending dispersed across institutions managing their own funds, so the Cour could not collect and assess all higher-education and research spending within the time available and instead estimated these amounts from the main actors' feedback (Procedures and methods, p.6-7). Because its resources are limited, France will have to choose between three budgetary paths: maintaining current funding and securing it beyond 2025 or 2030, increasing the funds allocated to sustain the "war of attrition" underway, or redirecting resources toward other deeptech priorities and accepting a loss of sovereignty over the quantum computer (Synthese, p.12). Almost all of the EUR 1 billion committed to quantum computing under the 2021-2025 national quantum strategy comes from the time-limited France 2030 investment plan rather than a permanent budget line. The Cour recommends that, "from the start of the 2027 academic year, the training offer be reinforced on the 'architecture', 'error correction' and software-stack components, as well as on the interface between classical computing and quantum computing" (Recommendations, no.4, p.13), noting that "uncertainty over part of the funding from the start of the 2028 academic year weighs on the durable adjustment of the training offer" (Synthese, p.11). The French quantum-computing sector "also suffers from a deficit of private investment, as European private actors have a greater aversion to risk than their North American counterparts"; while public support was essential to launch the sector, "the amounts needed to move to the industrial phase now exceed the State's financial capacities", making the mobilisation of private financing a critical issue (Synthese, p.11). The Cour recommends ensuring "exhaustive and up-to-date monitoring of companies in the strategic quantum sector, in coordination with the SGPI" (Recommendations, no.5, p.13), against a backdrop in which the sector's "phase of concentration, and sometimes of predation, of these companies has begun" (Synthese, p.11). Beyond the funding-level choice, France must also decide its strategic positioning - specialising in a particular segment as the Netherlands or Finland have done, positioning itself as a hub as the United Kingdom has chosen, or accepting technological dependency on a dominant foreign actor as several countries are doing with respect to the United States (Synthese, p.12); "any support will have to pursue a clearly identified strategic objective so that public financing devoted to the emergence of a sector is not captured by other powers" (Synthese, p.12). The Cour recommends building, by 2028, "targeted industrial partnerships at European scale, where appropriate with country specialisation" (Recommendations, no.6, p.13).