Making the case
The business case: freeing up the money
The money for a sovereign stack is largely already being spent. The question is whether it buys rented dependency or lasting UK capability.
Where the money is today
A few examples from the Body of Knowledge. Contract values are ceilings over different periods and are not additive.
~£1.9bn
public-sector spend on Microsoft licences in 2024/25 (The Register, 2025)
£774m
NHS five-year Microsoft 365 agreement (about £155m a year) (Digital Health, 2023)
up to £2.4bn
HMRC enterprise CRM contract with Salesforce, 10+5 years (CX Today, 2026)
£473m
HMRC ten-year AWS hosting contract (The Stack, 2026)
Four ways to free it up
None of these needs new money to start. Together they turn existing spend into UK capability.
1. Redirect, don’t add
Ring-fence a fixed share of existing licence and cloud spend for UK organisations that harden, maintain and support the open components the public sector depends on. Illustratively, 5% of public-sector Microsoft licence spend alone would be about £95m a year; 10% about £190m. (The Register, 2025)
Illustrative arithmetic on the ~£1.9bn figure, not a forecast.
The model exists: Germany's Sovereign Tech Agency has invested about €41m since 2022 in maintenance and security work on 118 critical open-source technologies (Sovereign Tech Agency, 2026).
2. Use every renewal
Large agreements are renegotiated on known dates, including the Jisc agreement with Microsoft for universities, which runs to the end of 2026. Each renewal is a chance to require open formats, customer-held keys, tested exit and a price that reflects credible alternatives. (Jisc, 2024)
3. Build once, use everywhere
Shared open components remove duplicated spend across hundreds of organisations. GDS estimated GOV.UK Notify saved £175m over five years; in the US, agencies spent about $32.5m on Login.gov against $209m on commercial identity products over the same period. See UK-01 and OA-02. (Government Digital Service, 2026; Federal News Network, 2026)
4. Price exit into every contract
Contracts that guarantee data export in open formats and a tested exit plan lower the cost of the next change and strengthen the public sector’s hand at every negotiation.
Redirect it into UK capability, year by year
Of £4.8bn a year in the contracts we could source, 86% goes to suppliers ultimately owned outside the UK (where the money goes). We propose redirecting a rising share of public-sector technology spend into UK contracts, skills and intellectual property, one renewal at a time, reaching 30% in year five. Total spend is about £26bn a year (Department for Science, Innovation and Technology, 2025), so every 1% redirected is about £260m a year and 30% is about £7.8bn.
| Year | Share of renewing contract value redirected | About a year, if applied to all spend | Where it goes first |
|---|---|---|---|
| Year 1 | 6% | £1.6bn | Open-source hardening and support fund; identity, collaboration and storage pilots on UK-operated infrastructure; spend baseline published. |
| Year 2 | 12% | £3.1bn | UK-operated open cloud on standard frameworks; maintainer apprenticeships and graduate places in every redirected contract. |
| Year 3 | 18% | £4.7bn | Shared sector components (case management, records, payments) built once on open standards with public IP. |
| Year 4 | 24% | £6.2bn | Open desktops where they fit; UK-hosted AI models for public-sector use. |
| Year 5 | 30% | £7.8bn | Coalition reference stack maintained with allies; UK firms exporting services built on it. |
Illustrative, not a forecast. Percentages apply to contract value falling due for renewal each year, so nothing is broken mid-contract.
60%
UK-delivered contracts
Open components and services operated in the UK by UK teams, in lots small enough for UK firms and SMEs to win.
25%
Skills
Apprenticeships, maintainer pathways and training on the shared stack, through schools, universities and the BBC.
15%
Intellectual property
R&D and code owned by the public sector or released under open licences, so the asset stays when the contract ends.
An illustrative split of each redirected pound.
How 30% can happen within the rules
Procurement law does not let a public body reserve contracts for UK companies as such: the Procurement Act 2023 prohibits discriminating against suppliers from countries covered by the UK's trade agreements (UK Parliament, 2023). Other countries get to sovereign outcomes through what they require, not who they favour.
Set security requirements for sensitive data
France requires particularly sensitive state data to sit on clouds qualified to SecNumCloud, which demands EU-based control and immunity from non-EU laws such as the US CLOUD Act; this has been policy since 2021 and law since 2024. The requirement is about control and jurisdiction, not nationality. (Qovery, 2026)
Score sovereignty in the tender
The European Commission is buying up to EUR 180m of sovereign cloud by assessing providers against eight sovereignty objectives with minimum assurance levels, including legal, operational, supply-chain and technological openness. (European Commission, 2025)
Reserve smaller contracts
Below the treaty thresholds, central government bodies may run competitions reserved to suppliers based and operating in the UK, or in a single county, and to SMEs and social enterprises. (Cabinet Office, 2025)
Use the renewal calendar
Large agreements are renegotiated on known dates. Each renewal can require open formats, customer-held keys, tested exit and UK operation where security needs it, and can carve out lots that UK firms can win. (Jisc, 2024)
Buy outcomes the UK keeps
Contracts funded by redirected money should leave intellectual property with the public sector or under open licences, and carry skills and social value commitments, which the National Procurement Policy Statement already asks for. (Fieldfisher, 2025)
Follow defence’s lead
The Defence Industrial Strategy already commits to prioritising British-based businesses and to spending at least 10% of the equipment budget on novel technology. (Ministry of Defence, 2025)
Illustrative, not legal advice. Each lever needs procurement and legal advice for the contract in question. Progress is measured each year in the index, through the UK capability and UK value capture dimensions.
What it costs: be honest
- Transition is not free. Schleswig-Holstein reports more than €15m in licence savings against a €9m one-off investment, and its rushed email cutover caused outages (Staatskanzlei Schleswig-Holstein, 2025).
- Under-resourced change reverses. Freiburg's move away from Microsoft Office saved about €800,000 in licences but a review estimated €2.5m in lost productivity, and the city went back (Computerwoche, 2012). Munich's return to Windows was estimated at €86.1m over six years (heise online, 2017).
- "Sovereign" hybrids cost more and change less. Locally operated versions of US clouds carry an expected premium of 10–20% while leaving code and supply chain unchanged (heise online, 2024).
- Done well, it pays. The French Gendarmerie reported a total cost of ownership about 40% lower on its open desktop estate (Hillenius, G., 2013), and Valencia reported about €36m saved over nine years with its schools Linux distribution (Vilas Gomez, A., 2024).
Price the risk of doing nothing
- Outage concentration. A single vendor's faulty update took GP systems offline nationally in July 2024 (Digital Health, 2024).
- Ownership change. Specialist suppliers are being bought by private equity and overseas owners; even government's joint-venture data centres sit with a US fund exploring a sale (DatacenterDynamics, 2025).
- Big-bang central programmes fail. The NHS National Programme for IT and GOV.UK Verify are reminders to start small, reuse what works and avoid single points of failure (National Audit Office (reported by Digital Health), 2013; National Audit Office, 2019).
- Weak negotiating position. Without credible alternatives, every renewal is a price-taker's renewal.
Structuring the case
Public investment decisions in the UK follow HM Treasury's five-case model (HM Treasury, 2022). A sovereign stack case maps onto it directly:
| Case | The question | What the Body of Knowledge provides |
|---|---|---|
| Strategic | Why act now? | Dependency, ownership change and continuity evidence; the twelve-dimension baseline |
| Economic | Which option gives best value? | Case-study savings and costs; value-capture and capability scores |
| Commercial | Can the market deliver, and on what terms? | Renewal windows, buying routes, UK and allied suppliers, exit terms |
| Financial | Is it affordable? | Existing spend that can be redirected; transition costs from comparable programmes |
| Management | Can it be delivered? | Lessons from what worked and what reversed; phased horizons |