CoCounsel (Thomson Reuters)
Overview
CoCounsel is Thomson Reuters' AI legal workflow platform (acquired from Casetext in 2023). It combines AI with Westlaw and Practical Law to support research, drafting, redlining, and document analysis. Available as both a Microsoft Word add-in and a web portal. Thomson Reuters announced in February 2026 that CoCounsel had passed one million users, and the line-up now spans CoCounsel Legal and CoCounsel Essentials for legal work plus CoCounsel Tax and CoCounsel Audit & Accounting.
Key Features
Deep Research (Agentic Research)
Instead of answering one prompt at a time, it builds and executes multi-step research plans across Westlaw content and returns a structured memo with proper citations. It is the headline capability of CoCounsel Legal.
Westlaw Integration (CoCounsel's Key Strength)
Integration with Thomson Reuters' Westlaw — one of the world's largest legal research databases — so answers stay grounded in verified primary law.
Practical Law Integration
Integration with Practical Law (practical guides) for practice-oriented legal information.
Practice Management Integrations
A March 2026 integration with the Smokeball practice management platform opened CoCounsel to smaller firms that do not hold a standalone Westlaw subscription.
Microsoft Word Add-In
AI features directly in Word:
- Contract review
- Drafting assistance
- Redlining
- Document analysis
Integrates AI without disrupting existing lawyer workflows.
Core Skills
- Summarize — long document summaries
- Search a database — internal database search
- Extract contract data — extract data from contracts
- Review documents
- Prepare for deposition
Pricing
| Configuration | Monthly | Highlights |
|---|---|---|
| CoCounsel Core (Westlaw add-on) | ~$225/user | No case law search; requires a separate Westlaw subscription |
| CoCounsel Legal (self-serve) | ~$637-$784/attorney | Current flagship tier, includes Deep Research |
| Westlaw Advantage + CoCounsel Essentials | ~$639/user | Bundled with Westlaw |
| Add-on rate at scale | $100-$200/user | Volume discounting |
CoCounsel is sold as part of the Westlaw ecosystem rather than standalone, so the realistic all-in cost lands at $300-$600+ per user per month once Westlaw is counted. Still cheaper than Harvey, but a multi-thousand-dollar annual commitment.
Typical Use Cases
- Case law research (Westlaw-integrated)
- Research memos via Deep Research
- Contract drafting (inside Word)
- Due diligence
- Document summarization
- Deposition prep
Strengths
- ✅ Deep Research runs multi-step research plans automatically
- ✅ Westlaw + Practical Law integration
- ✅ Microsoft Word add-in for existing workflows
- ✅ Thomson Reuters reliability and citation grounding
- ✅ Cheaper than Harvey and reachable for mid-size firms
- ✅ One million users and a line-up extending into tax and audit
Weaknesses
- ❌ Effectively bundled with Westlaw (Core alone cannot search case law)
- ❌ CoCounsel Legal runs $637-$784/month — far above the legacy add-on
- ❌ Less powerful than Harvey Vault (100K document analysis)
- ❌ Depends on Thomson Reuters ecosystem
- ❌ Limited Japanese law support