CoCounsel
CoCounsel is a generative AI assistant for legal professionals, launched in 2023 by Casetext and now owned and operated by Thomson Reuters.
Publisher review
CoCounsel is a generative AI assistant for legal professionals, launched in 2023 by Casetext and now owned and operated by Thomson Reuters. It is designed to augment—not replace—lawyers, paralegals, and tax or audit professionals by automating research, document review, contract drafting, and memo generation. The tool targets both large law firms and smaller practices, with Thomson Reuters positioning it as central to its enterprise AI strategy in 2025. Over 1 million professionals have used CoCounsel, and it supports 53 countries and 300 professional service firms, including multinational corporations and boutique firms. It is valued at $5B as of June 2025, reflecting rapid adoption across North America, Europe, and APAC.
CoCounsel generates expert-level output from plain English queries, grounded exclusively in authoritative Westlaw and Practical Law content. It provides verifiable answers with citations, reducing the risk of unsubstantiated claims. Key capabilities include document review, contract drafting, legal research, memo generation, and Deep Research for thorough legal analysis. Users can access an expert-created prompt library and connect tasks, tools, and content for complex workflows. However, practical use reveals limitations: users report that prompts require excessive detail, and large documents must be split into 100-page increments to avoid AI errors, making the tool less efficient for high-volume document review.
CoCounsel competes directly with Harvey AI, another legal AI platform serving over 300 firms across 53 countries. Harvey AI targets BigLaw with deep research workflows and broader data sources, including real-time tax and public company disclosures. CoCounsel leans more heavily on Thomson Reuters’ proprietary content and integrates tightly with existing Thomson Reuters tools, such as Westlaw and Practical Law. While Harvey AI has raised $300M in Series E funding and is valued at $5B, CoCounsel benefits from Thomson Reuters’ established distribution and trust among legal professionals, but lacks features like deposition analysis, judge or lawyer analysis, and real-time evidence integration that Harvey AI may offer.
Honest trade-offs include high cost, especially for larger firms, and limited trial preparation workflows. Users on Reddit describe CoCounsel as the "worst assistant EVER" due to its cumbersome prompt requirements and inability to handle large documents without manual splitting. The tool also has no real-time evidence integration, no deposition analysis, and no judge or lawyer analysis, which can be critical for litigation. While it reduces hallucinations by grounding answers in Westlaw content, the potential for output errors remains, and the closed system only cites to Westlaw sources, limiting flexibility compared to ChatGPT for general drafting and brainstorming.
How it works
-
Plain English querying
Users input natural language questions; CoCounsel generates expert-level legal output with citations from Westlaw and Practical Law.
-
Document review and analysis
Review, summarize, compare, or generate timelines from uploaded documents, though large files must be split into 100-page chunks.
-
Contract drafting
Drafts contracts and legal memos using Thomson Reuters' authoritative content, integrated with existing legal workflows.
-
Deep Research
Conducts thorough legal analysis by connecting multiple tasks and sources, providing verifiable answers grounded in Westlaw.
-
Expert-created prompt library
Offers pre-built prompts for common legal tasks, reducing setup time for users unfamiliar with prompt engineering.
-
Complex workflow orchestration
Connects tasks, tools, and content to handle multi-step legal processes, such as combining research with drafting.
-
Westlaw and Practical Law grounding
All outputs cite only Thomson Reuters' proprietary databases, ensuring authority but limiting source diversity.
Strengths and trade-offs
Strengths
- Enhances legal research accuracy by grounding outputs in authoritative Westlaw and Practical Law content, reducing unsubstantiated claims.
- Integrates seamlessly with Thomson Reuters tools, allowing users to access CoCounsel within existing workflows like Westlaw.
- Supports complex multi-step workflows by connecting tasks, tools, and content, enabling thorough legal analysis through Deep Research.
- Used by over 1 million professionals across 53 countries and 300 professional service firms, demonstrating broad adoption and trust.
Trade-offs
- Requires excessive prompt detail and manual splitting of documents into 100-page increments, making it inefficient for large-scale review.
- Lacks trial preparation workflows, deposition analysis, and real-time evidence integration, limiting its utility for litigation.
- Pricing is expensive for larger firms, with paid plans starting at contact vendor, and no transparent per-user or consumption costs.
- Potential for hallucinations in output persists despite grounding in Westlaw, and the closed system only cites Thomson Reuters sources.
Pricing context
Freemium model with paid plans starting at contact vendor; no publicly listed per-user or consumption-based pricing.
Getting started with CoCounsel
-
Sign up for CoCounsel
Visit the Thomson Reuters CoCounsel website and click the sign-up button. Provide your professional email, firm details, and accept the terms. Choose the freemium tier or contact sales for a paid plan.
-
Connect Westlaw credentials
Log into your Thomson Reuters account and authorize CoCounsel to access your Westlaw and Practical Law subscriptions. This links the tool to authoritative legal content for grounded outputs.
-
Configure document handling
Set your document upload preferences in the settings panel. Note that files over 100 pages must be split into smaller chunks before uploading to avoid processing errors.
-
Run a legal research query
Type a plain English question into the main input field, such as 'Summarize the key holdings in Smith v. Jones.' CoCounsel will return a cited answer from Westlaw. Verify the citations for accuracy.
-
Schedule recurring reviews
Use the workflow orchestration feature to set up automated document review tasks. Define a schedule and connect multiple steps, such as research followed by drafting, to streamline your daily legal processes.
Frequently Asked Questions
What is CoCounsel and who is it for?
CoCounsel is a generative AI assistant for legal professionals launched in 2023 by Casetext and now owned by Thomson Reuters. It helps lawyers, paralegals, and tax or audit professionals automate research, document review, contract drafting, and memo generation. Over 1 million professionals have used it.
What are the main features of CoCounsel?
CoCounsel offers plain English querying with citations from Westlaw and Practical Law, document review and analysis, contract drafting, Deep Research for thorough legal analysis, an expert-created prompt library, and complex workflow orchestration. All outputs are grounded in Thomson Reuters' authoritative content.
How much does CoCounsel cost?
CoCounsel uses a freemium model with paid plans starting at contact vendor. There is no publicly listed per-user or consumption-based pricing. Users on Reddit describe it as expensive, especially for larger firms, but exact costs are not disclosed by Thomson Reuters.
What are the main limitations of CoCounsel?
Users report that prompts require excessive detail and large documents must be split into 100-page increments to avoid errors. CoCounsel lacks trial preparation workflows, deposition analysis, judge or lawyer analysis, and real-time evidence integration, making it less efficient for litigation tasks.
How does CoCounsel compare to Harvey AI?
CoCounsel relies heavily on Thomson Reuters' proprietary Westlaw and Practical Law content, while Harvey AI uses broader data sources including real-time tax and public company disclosures. Harvey AI targets BigLaw with deep research workflows and has raised $300M in funding. Both are valued at $5B.
Is CoCounsel good for small law firms?
CoCounsel supports both large law firms and smaller practices, with Thomson Reuters positioning it for enterprise AI strategy. However, its high cost and cumbersome prompt requirements may be challenging for small firms. It is used by 300 professional service firms across 53 countries.
Alternatives
How CoCounsel compares
Direct head-to-head against 3 competitors. Picked by 7wData.
CoCounsel
- Pricing
- Freemium model with paid plans starting at contact vendor; no publicly listed per-user or consumption-based pricing.
- Target
- CoCounsel is a generative AI assistant for legal professionals, launched in 2023 by Casetext and now owned and operated by Thomson Reuters.
- Strength
- Enhances legal research accuracy by grounding outputs in authoritative Westlaw and Practical Law content, reducing unsubstantiated claims.
- Watch for
- Requires excessive prompt detail and manual splitting of documents into 100-page increments, making it inefficient for large-scale review.
CPA Pilot
- Pricing
- $19/user/month
- Target
- CPAs needing client-ready deliverables
- Deployment
- Cloud
- Strength
- Turns research into sendable, cited drafts with tax software guidance
- Watch for
- Niche focus on tax practice workflows
TheLawGPT
- Pricing
- $19.99-$89.99/month
- Target
- Solo lawyers and small firms
- Deployment
- Cloud
- Strength
- Legal Q&A and document generation without Westlaw dependency
- Watch for
- Lacks deep case law analysis capabilities
Harvey
- Pricing
- $399-$2,400/seat/month
- Target
- Large law firms
- Deployment
- Enterprise
- Strength
- Lexis integration for complex litigation
- Watch for
- High cost and inconsistent demo quality
User reviews
No user reviews yet. Be the first to write one.
Sources
Reporting on this tool draws on these publicly available sources.