Plainsight AI Assistant vs Microsoft 365 Copilot: The Honest Comparison
The two overlap more than people expect. Nine capabilities side by side and what per-seat versus flat platform pricing means at 250, 1,000 and 2,500 people.
The overlap is real. So are the differences.
Microsoft 365 Copilot and the Plainsight AI Assistant overlap more than people expect. Both answer questions from your documents. Both live inside your working day. Where they differ is worth understanding before budget goes in either direction, so here is the comparison written straight.
The short version: Copilot is a licence per user, inside one vendor’s ecosystem. The Plainsight AI Assistant is one platform for your whole organisation, with any model and any system connected to it. That is the difference this page walks through.
Capability by capability
| Capability | Microsoft 365 Copilot | Plainsight AI Assistant |
|---|---|---|
| Inside Word, Excel, PowerPoint, Outlook, Teams | ✓Native inside Word, Excel, PowerPoint, Outlook and Teams. | ✓Reads and acts across mail, calendar, Teams, files and tasks through Microsoft Graph, plus its own workspace. |
| Answers from your documents, with citations | ✓Over Microsoft 365 content, through Graph and the semantic index. | ✓Over your own knowledge bases, with clickable citations and a panel showing what was searched. |
| Content outside Microsoft 365 | ~Possible through Graph connectors and Power Platform, licensed and configured as separate products. | ✓Any system with an API or MCP server. ERP, CRM, ticketing, internal databases, connected as part of the integration scope. |
| Choice of model | ~OpenAI models, with Anthropic Claude added during 2025. On EU tenants Claude is off by default and sits outside Microsoft's EU Data Boundary, so enabling it is a data residency decision. Either way, one model decision for the whole tenant. | ✓Azure OpenAI, Anthropic, Mistral or open models, chosen per department and switched with a toggle. When a better or cheaper model arrives, you move without a rebuild or a migration. |
| Separate knowledge and rules per department | ~Requires agents built in Copilot Studio, governed and licensed separately. | ✓Built in. Isolated knowledge base, own system prompt, own model and own access boundary per department. |
| Scheduled standing tasks | ~Through agents, with setup and licensing per agent. | ✓Automations: a standing prompt on a schedule, results delivered into your chat, run or retry on demand. |
| Where it runs | ~Microsoft's service, inside your tenant boundary, on Microsoft's terms. | ✓Your own cloud tenant on Azure, AWS or Google Cloud, or fully on-premises. We manage the platform and never access your data. |
| Admin view of usage and cost | ✓Copilot admin reporting inside the Microsoft admin centre. | ✓Usage, cost and budget per department, model management, audit trail and branding, in one control centre. |
| Price shape | €Per user per month, on top of a qualifying Microsoft 365 plan. Cost rises with every person you give access to. | €Flat platform fee per company size, plus your own infrastructure at cost. Cost does not move when you hire. |
Where Copilot stops
Everything outside Microsoft 365
Copilot answers over what an individual can already reach in Microsoft 365. It does not give the organisation a governed, cross-system view of what it knows, including the knowledge sitting in ERP, CRM and internal systems. That is the gap a platform fills.
The cost logic, briefly
Per-seat pricing makes adoption the thing you pay for, which creates pressure to ration access to the people who already know what to ask. Platform pricing removes that maths. Three scenarios, so you can see roughly where your own number lands.
250
people with access
1,000
people with access
2,500
people with access
Per-seat figures use €30 per user per month, Microsoft lists 30 dollars on an annual term, and they exclude the Microsoft 365 plan that Copilot requires underneath it. Plainsight figures are the public platform bands, with a one-time setup fee from €2,500. Infrastructure means your own compute and token usage, billed transparently at cost. Above 2,000 people the band is scoped to your setup rather than listed.
One platform for the whole organisation, instead of a licence per vendor per user. Don’t let a per-seat licence decide your architecture.
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