What Is CoCounsel? Thomson Reuters' Legal AI Explained
A clear guide to CoCounsel: its features, pricing, Casetext roots, and the firms it fits best.
CoCounsel is an AI legal assistant from Thomson Reuters that helps lawyers research, draft, and review documents. It is grounded in Thomson Reuters content like Westlaw and Practical Law, not the open web.
CoCounsel started as a Casetext product and became part of Thomson Reuters after a $650 million acquisition. This guide explains what CoCounsel does, what it costs, and who it is for.
What is CoCounsel?
CoCounsel is Thomson Reuters' AI assistant built for legal research, drafting, and document analysis. It answers legal questions using trusted, sourced content instead of generic web results.
Because CoCounsel is grounded in Westlaw and Practical Law, its answers include citations you can trace and check. This helps lawyers avoid the fake-citation risk of generic AI.
CoCounsel works inside tools lawyers already use, including Westlaw, Microsoft 365, and document management systems. Thomson Reuters reports over one million professional users across 107 countries.
- Deep legal research grounded in Thomson Reuters content
- Document review and analysis across large file sets
- Guided drafting workflows for policies, complaints, and discovery
- Knowledge search across your own uploaded documents
Weighing CoCounsel against other legal AI tools? Get a vendor-neutral fit check before you commit to a multi-year Thomson Reuters contract.
Book a ConsultationWhat does CoCounsel do? Key features
CoCounsel does legal research, document review, and guided drafting in one connected assistant. It also runs multi-step "agentic" workflows that carry out predefined legal tasks.
Its Deep Research feature reasons across thousands of documents and returns structured analysis. Guided workflows include drafting a complaint, a privacy policy, and discovery requests.
CoCounsel connects to Westlaw and Practical Law, which sets it apart from standalone tools. That integration is a real advantage if your firm already pays for Westlaw.
- Deep Research: structured analysis across large document sets
- Agentic guided workflows for common drafting tasks
- Knowledge Search across firm documents and the knowledge graph
- Native links to Westlaw, Practical Law, and Microsoft 365
CoCounsel pricing: how much does CoCounsel cost?
CoCounsel pricing ranges from about $104 to $639 per user per month, depending on the plan and add-ons. Thomson Reuters offers several tiers, and larger firms are quoted by sales.
Solo and small firms (up to 10 attorneys) can get a price through an online configurator. It bases cost on firm size, jurisdiction, and contract length.
A common CoCounsel Core plan runs about $4,500 per user per year, or roughly $225 per user per month. Bundles that include Westlaw coverage cost more.
CoCounsel, Casetext, and Thomson Reuters
CoCounsel began as the flagship AI product of Casetext, a legal research startup. Thomson Reuters acquired Casetext in 2023 for $650 million and made CoCounsel its core AI brand.
That lineage matters because CoCounsel now blends Casetext's early AI work with Thomson Reuters' trusted legal content. The result is an assistant with deep research roots.
Today CoCounsel is Thomson Reuters' main legal AI offering. It sits at the center of the company's push into professional-grade AI.
Who is CoCounsel best for?
CoCounsel is best for firms that already rely on Westlaw and want research plus drafting in one place. In-house teams and litigation-heavy practices benefit most.
One real fit note: CoCounsel's value is highest when you use Westlaw. If your firm does not, you pay for content integration you may not fully tap.
For a broader look at legal AI options, see our guide to AI for legal teams and our contract review tools comparison.
CoCounsel review: strengths and limits
CoCounsel earns solid reviews for trusted research and traceable citations. Lawyers value that answers link back to Thomson Reuters content they already rely on.
The main limits are cost and bundling. Prices climb once Westlaw coverage is added, and multi-year terms are common, so read the contract carefully.
CoCounsel also works best inside the Thomson Reuters ecosystem. Firms that do not use Westlaw may see less benefit from its grounded-content design.
- Strength: research grounded in trusted, citable content
- Strength: deep integration with Westlaw and Microsoft 365
- Limit: cost rises quickly with Westlaw bundles
- Limit: value is highest inside the Thomson Reuters stack
CoCounsel alternatives and how it compares
CoCounsel competes with Harvey, Legora, and Spellbook, among others. Each tool leans toward a different strength and firm size.
Here is a quick comparison. For the full list, see our Harvey AI alternatives guide and the head-to-head Harvey vs CoCounsel.
- CoCounsel: research + drafting grounded in Westlaw and Practical Law
- Harvey: enterprise legal AI with broad custom agents; see Harvey AI explained
- Legora: collaborative legal AI, strong in Europe; see Legora explained
- Spellbook: Word-native contract drafting for smaller teams; see Spellbook explained
- Lexis+ AI: LexisNexis's research-grounded rival to CoCounsel; see Lexis+ AI explained
Frequently Asked Questions
- CoCounsel costs roughly $104 to $639 per user per month depending on the plan. A common CoCounsel Core plan runs about $4,500 per user per year, and Westlaw bundles cost more.
- CoCounsel is Thomson Reuters' AI legal assistant for research, drafting, and document review. It is grounded in trusted content like Westlaw rather than generic web results.
- Thomson Reuters owns CoCounsel. It started as a Casetext product, and Thomson Reuters acquired Casetext in 2023 for $650 million.
- CoCounsel is worth it for firms that already use Westlaw and want research plus drafting in one place. Firms without Westlaw may not fully use its grounded-content advantage.
- CoCounsel is best for research-heavy and litigation practices that rely on Westlaw. Its traceable citations and guided drafting workflows suit both in-house and firm lawyers.
- CoCounsel reduces fake-citation risk by grounding answers in Thomson Reuters' editorial content. Citations are traceable and checkable, unlike generic AI chatbots.
- CoCounsel is the evolution of Casetext's AI product after Thomson Reuters acquired Casetext in 2023. It now combines that early AI work with Thomson Reuters' legal content.
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