Side by side
| Factor | On-premise or private cloud, open-weight models | UK-region cloud AI service | Copilot inside your Microsoft 365 tenant |
|---|---|---|---|
| Where data is processed | Your hardware or a private environment you control | The provider's UK region, if regional processing is selected | Within your tenant's data boundary, under Microsoft's terms |
| Model capability | Good open models, usually behind the largest hosted models | Access to the most capable hosted models | Strong for everyday office work |
| Upfront cost | High: hardware or reserved capacity | Low: pay as you use | Licence per user |
| Skills needed | High: hosting, security, updates and monitoring | Moderate: configuration and governance | Moderate: permissions and training |
| Time to first use | Weeks to months | Days to weeks | Days, once permissions are fixed |
| Main risk | Cost and keeping it secure and up to date | Processing location and provider jurisdiction | Oversharing: it surfaces whatever staff can already access |
When on-premise is the right choice
- Data that must not leave your own environment under any contract.
- Steady, high-volume workloads where owning capacity costs less over time.
- Teams with the skills to run and patch the platform, or a hosting partner to do it.
When UK-region cloud is the right choice
- Most organisations, most of the time, once data is classified.
- When you need the most capable models without buying hardware.
- When you can choose regional processing and the provider's terms meet your risk assessment.
Why many organisations choose both
A common pattern is a small, tightly controlled environment for the most sensitive data, and UK-region cloud or Copilot for everything else. The deciding step is data classification: once you know what each dataset is, the right place for each AI use is usually clear.
Questions to ask any provider
- Where are prompts and outputs processed, and is that the same place as storage?
- Are prompts or outputs used to train models?
- How long are logs kept, and who can see them?
- Which law applies to the provider, and how are government access requests handled?
- What happens to our data when the contract ends?
How to start, and what it costs
- Free AI Readiness Audit. 15 questions, about 5 minutes, including AI governance. Take the audit.
- AI and Copilot Discovery Day. One day with a consultant, £950 + VAT, fixed. For a public body this is where we classify your data, map where each AI tool processes it and agree the rules. See what is included.
- Implementation. Value based, scoped and quoted after the Discovery Day.
What we do and do not do
We help you classify data, compare options for your situation and set up governance and pilots. We do not sell hardware or hosting, so our advice is not tied to one option. If you choose on-premise, a specialist hosting partner should run the platform. Back to sovereign AI for UK organisations.
Questions we are often asked
Is on-premise AI more secure than cloud AI?
Not automatically. It gives more control, but security depends on how well it is run, patched and monitored. A well-configured cloud service can be safer than a poorly run server.
Are open-weight models good enough?
For many tasks, such as summarising and drafting, yes. For the hardest reasoning tasks, the largest hosted models are usually stronger. Test with your own work before deciding.
Does UK-region cloud mean data never leaves the UK?
Only if the specific service processes prompts in the UK and its terms say so. Check processing, not only storage, and check support and logging arrangements.
Which option is cheapest?
For occasional use, cloud. For steady, high-volume use with in-house skills, on-premise can cost less over time. Model the real volumes before deciding.