Companies evaluating AI for internal operations face a basic choice: subscribe to a hosted service like ChatGPT Enterprise, or deploy a language model on infrastructure you control. The sales pages for both options make their case convincingly. But the decision has real consequences for data security, cost at scale, and what you can actually build. This is an honest comparison based on what we have seen deploying both approaches for businesses across healthcare, legal, financial services, and professional services.
What ChatGPT Enterprise gives you
ChatGPT Enterprise costs $60 per user per month (as of early 2026). For that you get GPT-4 class models with no usage caps, a company workspace with admin controls, SSO integration, and a data processing agreement that says OpenAI will not train on your conversations. It is fast to set up. Buy licenses, invite your team, and people start using it the same day.
For general productivity use (drafting emails, summarizing documents, brainstorming, research), it works well. The interface is familiar, the models are capable, and the learning curve for employees is minimal. If your goal is giving your team a better search and writing tool, ChatGPT Enterprise is a reasonable choice.
Where hosted AI falls short
The limitations show up when you move beyond general productivity into actual business operations. Three issues come up repeatedly.
First, data leaves your environment. Even with a data processing agreement, your information travels to OpenAI's infrastructure for processing. For companies in healthcare (HIPAA), financial services (SOC-2, PCI), or legal (attorney client privilege), this creates compliance exposure that no contract fully resolves. The data exists on someone else's servers, processed by someone else's systems, subject to someone else's security practices.
Second, you cannot customize the model. ChatGPT Enterprise gives you the same model everyone else gets. You can use custom GPTs with uploaded documents, but you cannot fine tune the underlying model on your proprietary data. For tasks that require deep understanding of your specific terminology, processes, or domain knowledge, the generic model produces generic results.
Third, cost scales linearly with users. At $60 per user per month, 100 users costs $72,000 per year. 500 users costs $360,000 per year. The per-user model means your AI costs grow directly with headcount regardless of how much each person actually uses the tool.
What private LLM deployment gives you
A private LLM runs on infrastructure you control. That can be your own servers, your cloud account (AWS, Azure, GCP), or a dedicated hosting environment. The model processes data without it ever leaving your network boundary.
The advantages are specific. Your data never touches third party systems. You can fine tune the model on your proprietary data to get better results for your specific use cases. You control the model version, update schedule, and behavior. And your costs scale with compute usage, not user count. A private deployment that handles 10 users and 10,000 users uses the same infrastructure if the request volume is similar.
The tradeoffs are also specific. Setup takes weeks, not minutes. You need someone to manage the infrastructure (or a partner to do it). The upfront cost is higher. And smaller open source models, while capable, do not match the largest commercial models on every task.
When private deployment makes sense
- You handle protected health information (PHI), financial records, legal documents, or trade secrets. The compliance burden of sending this data to a third party API is real and ongoing.
- You need AI agents that take action in your systems, not just answer questions. Agents that process invoices, manage patient records, or handle legal document review need deep integration with your internal tools. That integration is easier and more secure on private infrastructure.
- You have more than 200 users. At that scale, the per-user subscription cost often exceeds the total cost of private infrastructure.
- You want to build proprietary AI capabilities. Fine tuned models trained on your data become a competitive advantage. That is only possible with models you control.
When ChatGPT Enterprise makes sense
- You have fewer than 50 users and the primary use case is general productivity.
- Your data is not subject to regulatory compliance requirements.
- You do not need AI to take action inside your business systems. You just need it to assist with writing, research, and analysis.
- Speed of deployment matters more than long term cost optimization.
The hybrid approach
Many companies end up with both. ChatGPT Enterprise or a similar tool for general productivity (everyone gets it), and private LLM deployment for specific operational workflows where data sensitivity and deep integration matter. The key is being intentional about which data goes where and which workflows run on which infrastructure.
For a more detailed technical comparison, see our side-by-side at /compare/private-llm-vs-public-api. CloudNSite specializes in private LLM deployment for businesses that need their AI to operate inside their own security boundary. Our deployment approach includes infrastructure setup, model selection and fine tuning, integration with your existing systems, and ongoing management. Browse our approach at /solutions/private-llm-deployment or take the AI readiness assessment at /tools/ai-readiness.