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Stitex
Infrastructure

On-Premise LLM vs. Cloud AI: The Real Cost Comparison

Short answer: it comes down to headcount and what's in the prompts. Under about 10 users with nothing sensitive to hide, cloud AI is cheaper and simpler. Past that, or the moment contracts, client records, or trade secrets enter the picture, an on-premise LLM pays for itself and closes a leak risk cloud can't. Here's the math over three years.

July 20, 202613 min readStitex Technologies

On-Premise LLM vs. Cloud AI: What’s Actually Different

A cloud AI is someone else’s computer. Every prompt your team sends travels over the internet to the provider’s servers, usually overseas, gets processed there, and comes back. You pay per request, and you’re trusting the provider with everything inside that request.

An on-premise LLM is an open-weight language model installed on your own server. Requests are processed inside the company; nothing goes out. You pay once for the hardware and setup, then it’s just electricity. You can unplug the server from the internet entirely — the model keeps working.

What Open-Source Models Can Actually Do in 2026

Three years ago, the gap between open and cloud models was a canyon. Today, workhorse open models in the 27-32B parameter class handle most everyday business tasks convincingly: answering from a knowledge base, reviewing contracts, drafting text and emails, reading spreadsheets, pulling data off scanned documents, working with code.

This isn’t a claim from a benchmark leaderboard — our own company runs on a local model in this class. It handles our call-transcript analysis, content generation, document review, and internal reporting. Frontier cloud models still have an edge in deep reasoning and hard coding problems, but for the routine 80% of the work, that gap barely matters anymore.

Which model size you actually need
We break down model classes, VRAM requirements, and ready-made server configurations with pricing in a separate guide on the on-premise AI server page — everything from compact 7B setups to data-center-scale rigs.

Head-to-Head Comparison

CriterionCloud (ChatGPT & similar)On-premise LLM
Where your data livesprovider's servers, often overseasinside your company
Pricingsubscription/tokens, scales with usageone-time hardware + setup
Data-protection compliancegray area, depends on the providercompliant by design
Works offlinenoyes, completely
Cutoff / sanctions riskbilling, access, provider policynone
Quality on hard tasksbest availablestrong; top-tier work via a hybrid setup
Time to get runningminutesweeks to deploy

Total Cost of Ownership: The 3-Year Math

Let’s run the numbers for a 30-person company that uses AI daily.

The cloud route

  • Corporate subscriptions: 30 people × ~₽2,500/mo (roughly $25-30) ≈ ₽75,000/mo (about $800),
  • Plus API costs for automation (bots, document processing): another ₽20,000-60,000/mo (about $200-650) at real usage volumes,
  • Three-year total: ₽3.5-5 million (roughly $40,000-55,000), and the bill keeps climbing as usage grows.

The on-premise route

  • A workhorse server for 30-50 users: ~₽800,000 (roughly $9,000) one-time, turnkey,
  • Power and upkeep: ~₽10,000-20,000/mo (roughly $110-220),
  • Three-year total: ~₽1.2-1.5 million (roughly $13,000-17,000); after that, it's just maintenance.

The break-even lands around 10-15 active users. Below that, cloud wins on price; above it, your own server pulls ahead, and the gap widens every year it runs. Once anything confidential enters the prompts, this stops being a pricing question at all.

When Cloud AI Is Enough

  • Fewer than 10 active users, and nothing sensitive shows up in the prompts,
  • Usage is occasional — a handful of queries a day, not a daily-driver tool,
  • You specifically need frontier-level reasoning or coding, and the data itself isn't confidential.

In these cases, the honest advice is: stay on cloud, but tighten the basics — company accounts instead of personal ones, a written policy on what never goes into a chat window, and a provider whose data-residency and retention terms you’ve actually read, not just clicked through.

When You Need an On-Premise Server

  • Regulatory requirements: personal data, banking or healthcare confidentiality, air-gapped environments — in Russia that means compliance with data-protection law 152-FZ; elsewhere it’s GDPR-style rules or a local equivalent,
  • Trade secrets in every prompt: contracts, client databases, cost structures, R&D,
  • Scale: dozens of employees using AI every day: cloud economics break down at that point,
  • Independence: your operations shouldn’t hinge on a foreign vendor’s uptime, or on how you’re allowed to pay them.

Hybrid: Getting the Best of Both

The setup we run ourselves and deploy for clients: the local model handles the bulk of the work inside your perimeter. For the rare task that genuinely needs a frontier cloud model, the request goes through a double pass of scrubbing — rules strip out names, account numbers, amounts, and identifiers first, then the local model checks that nothing slipped through. What leaves the building is an anonymized version of the task; the answer comes back into the perimeter, where context gets restored.

That way you get top-tier model quality on the 5% of tasks that actually need it, without trading away confidentiality on the other 95%.

Bottom Line

“On-premise LLM or ChatGPT” is really three questions: what’s in your prompts, how many people are using it, and what you’re willing to depend on. A small team with nothing confidential to hide is fine on cloud. A business with trade secrets, regulatory obligations, or 15+ daily active users comes out ahead on both security and cost with its own server — and a hybrid setup covers whatever top-tier work is left over.

Frequently Asked Questions

Is an on-premise LLM actually as good as ChatGPT?

Yes, for most day-to-day business work: answering from a knowledge base, reviewing contracts, drafting text, reading documents. Open models in the 27-32B class handle it well. Frontier cloud models still lead on deep reasoning and hard coding problems, but that's a minority of daily tasks.

How much does an on-premise AI server cost?

A workhorse server for 30-50 users runs roughly ₽800,000 (about $9,000) turnkey, plus ₽10,000-20,000/mo (about $110-220) for power and upkeep. At 15+ daily active users it typically beats cloud subscriptions within the first year or two.

Do we still need cloud AI once we have our own server?

Often yes, for the rare task that genuinely needs a frontier model. The way around that is a hybrid setup: rules and a local model strip out names, numbers, and identifying details before anything leaves the building, and a second pass checks nothing slipped through.

Let's run your numbers

Tell us about your use case and team size — we'll compare cloud vs. on-premise costs for your specific situation, honestly.