The business impact of Lexis+ AI on UK legal services
Key findings from Forrester Total Economic Impact™ studies examines the time and cost savings potential of Lexis+ AI. We look at what the results mean for the UK.
Key findings across the legal ecosystem
Forrester concluded that Lexis+ AI® delivered the following results to both US law firms and US corporate legal departments:
2.5 hours
Lexis+ AI saved lawyers at large US law firms 2.5 hours per week on routine drafting and legal research.
25%
Lexis+ AI reduced time spent on legal tasks at US corporate legal departments by 25%.
15-35%
Large law firms recovered between 15% and 35% of written-off time as a direct result of Lexis+ AI.
A UK-specific survey of Lexis+ AI found:
The use of artificial intelligence in legal services has skyrocketed in the UK, jumping from 46% to 61% between January and August of 2025. While adoption is surging, confidence and culture are lagging. Only 17% of lawyers say that AI is fully embedded in strategy and operations, with two-thirds reporting their organisation’s AI culture is slow or non-existent.
The commissioned Total Economic Impact™ studies conducted by Forrester Consulting on behalf of LexisNexis Legal & Professional provide a dual-lens view into this shift.
Findings show that law firms have the potential to improve profitability by increasing lawyer capacity and research efficiency, while reducing written-off billable hours and enabling focus on delivering the highest value services to their clients. Corporate legal departments are improving responsiveness to legal inquiries and reducing excess outside counsel spending, while meeting high standards for quality.
Failing to embed AI into existing workflows is not only a commercial risk. Our August 2025 survey of UK legal professionals suggested a clear talent retention risk for the firms that lag behind. Nearly one in five (18%) private practice lawyers and in-house counsel (19%) said they would consider leaving their organisation if it failed to adequately invest in AI. This figure rose to 26% among those at large law firms.
Firms that lead will move quickly. Success with AI won’t come from adoption alone, but from proving its impact, aligning it to strategy, and empowering people to use it with confidence and purpose.
The impact of AI for legal professionals
Time savings
for lawyers and staff in research, drafting, document preparation, and administrative tasks
Improved economic dynamics
due to increased capacity and ability to focus on higher value work
Competitive edge for talent
due to improved work-life balance and career advancement opportunities
Advanced security & quality of information
required by the legal field
Lexis+ AI for law firms and corporate legal departments
Lexis+ AI is a legal research, drafting, and insights solution that combines a generative AI assistant with LexisNexis content. Legal professionals benefit from conversational search, legal drafting, and document summarisation and analysis in the protected environment of the LexisNexis ecosystem.
For the purposes of the studies, Forrester focused on the capabilities of Lexis+ AI prior to the integration of the agentic AI assistant LexisNexis Protégé™.
Forrester methodology
To understand the benefits, costs, and risks associated with investment in Lexis+ AI, Forrester interviewed decision-makers at five large law firms and four corporations.
Based on the interviews, Forrester constructed Total Economic Impact™ frameworks, composite organisations, and ROI analyses. The composites are representative of the interviewees' experiences and are used to aggregate financial analysis.
The Total Economic Impact™ of Lexis+ AI for Large Law Firms
Law firms look to generative AI to enhance client service and foster innovation while supporting long-term profitability. In the Total Economic Impact™ of Lexis+ AI for Large Law Firms (May 2025), interviewed leaders at large law firms expressed that they feel growing pressure to adopt technologies that enable faster, more informed legal work and help their firms stay competitive without exposing them to additional risks.
For their analysis, Forrester constructed a composite organisation based on the experiences of five large law firms. The composite is a global law firm based in North America with US $1.5bn in annual revenue, 950 lawyers, 15 research staff, and a 25% profit margin.
While these ROI figures are representative of a select group of large US law firms, it hints at the time and cost savings potential of Lexis+ AI for the wider legal profession.
Benefits for law firms
In interviews with leaders at law firms, Forrester uncovered the following benefits from Lexis+ AI across a three-year analysis period:
- Time savings for senior associates and partners of 2.5 hours per week on drafting and research, which enabled them to take on more work for the firm
- Up to 35% reduction of previously written-off billable hours by junior lawyers
- Annual time savings of 225 hours for each research staff member
Unquantified benefits for law firms
In addition, law firm leaders noted several strategic benefits that, while not quantified in the study, were nonetheless significant to their organisations:
- Having a competitive edge in the market for talent
- Improving client delivery and increasing client satisfaction
- Increasing confidence in generative AI deployments from enhanced security and training support
Insights from the report
“What drove us to [invest in Lexis+ AI] is the belief that our clients will expect and the standard of service that we expect to deliver are both going to require that we utilize some sort of generative AI in the future, and that is a journey we wanted to get started on.”
“[My firm’s AI strategy] includes investing in training our lawyers who we seek to augment through this new technology rather than replace. We also see huge opportunities for productivity gains across all types of legal work as they integrate them into their daily workflows. [It leads to] lots of time savings.”
“It’s clear that AI — from the extractive world to the generative — offer the firm and our clients an unprecedented business opportunity, more efficiency in how we work, and more time to focus on strategic activities, such as enhancing client service, delivery and experiences.”
Get more insights
Download the Total Economic Impact™ of Lexis+ AI for Large Law Firms to:
- Understand the business impact of generative AI on leading law firms
- See how customers implemented their AI programmes
- Dive into the numbers and financial analysis
How Lexis+ AI is being used in the UK
“We want to be at the forefront of technology that delivers better client services. Lexis+ AI brings next-generation workflow management, speed, and efficiency into the core of our firm.”
“Lexis+ AI is designed specifically for lawyers. Context is built in, and it’s optimised to pull from the correct data sources. This setup was a no-brainer for us because we know the data is up to date, accessible, and relevant.”
The Total Economic Impact™ of Lexis+ AI for corporate legal departments
Corporate legal departments aim to leverage generative AI across their workflows to become more efficient and effective in serving internal clients. In the Total Economic Impact™ of LexisNexis Lexis+ AI for Corporate Legal Departments (June 2025), interviewed corporate legal leaders said their departments looked to Lexis+ AI to deliver operational efficiencies and meaningful value to internal clients and the larger organisation while meeting both accuracy and security standards.
For their analysis, Forrester constructed a composite organisation based on the experiences of four corporate legal departments. The composite is a global enterprise based in North America with $10bn in annual revenue and a corporate legal staff of 70 lawyers and 10 paralegals.
Benefits for corporations
In interviews with leaders at corporate legal departments, Forrester uncovered the following benefits from Lexis+ AI across a three-year analysis period:
- Up to 13% reduction in work handled with outside counsel, saving significant cost
- 25% reduction in annual time spent advising the business on legal inquiries, increasing capacity for lawyers
- 50% reduction in annual time for paralegals on administrative tasks
What customers are saying
“Our hypothesis was that we [can give] the attorneys [more cases] if we give them [Lexis+ AI] and a handful of other productivity tools, and we would not be effectively increasing their workload. In fact, their workloads might even decrease. We have a good sense that it’s working.”
“When you don’t have to spend so much time summarizing the documents, you are freed up to spend time on other parts of the deal.”
“[LexisNexis] has a very great trainer who we have access to. She’s been very helpful and critical in getting [users] started on Lexis+ AI.”
Get the full study
Download the Total Economic Impact™ of Lexis+ AI for Corporate Legal Departments to:
- Understand the business impact of generative AI on corporations
- See how customers implemented their AI programmes
- Dive into the numbers and financial analysis
A shared focus on high value legal work
The Forrester Total Economic Impact™ studies underscore how law firms and corporate legal departments, though structurally distinct, are arriving at similar outcomes through generative AI adoption:
- Greater efficiency
- Better use of internal resources
- Improved economic performance
- Emphasis on quality and high value work
Our analysis indicates that, while it may appear that corporate legal departments' reduced reliance on outside counsel could come at the expense of law firms, the Forrester studies suggest a different narrative:
- Corporate teams are cutting low-value spend—not high-value engagements—by handling more routine legal matters in-house
- At the same time, law firms are using generative AI to focus on delivering the highest value work to clients, rather than tasks that are not billable
- In both cases, legal professionals are shifting focus toward the highest-value services they can offer
Rather than working at cross-purposes, these trends reflect a shared emphasis on strategic, expert-led legal work.
These parallels further suggest that generative AI is becoming foundational to how legal organisations function. As the role of generative AI continues to evolve, legal leaders may want to consider how shared expectations across the market will shape future decisions about talent, technology, and client service.
Download the studies
Read the in-depth Forrester Total Economic Impact™ studies of Lexis+ AI for Large Law Firms and Corporate Legal Departments to:
- Explore how peers are using Lexis+ AI to drive economic impact
- Dive into the financial analysis
- Learn more about Forrester’s methodology
About LexisNexis Legal & Professional
LexisNexis® Legal & Professional provides legal, regulatory, and business information and analytics that help customers increase their productivity, improve decision-making, achieve better outcomes, and advance the rule of law around the world. As a digital pioneer, the company was the first to bring legal and business information online with its Lexis® and Nexis® services. LexisNexis Legal & Professional, which serves customers in more than 150 countries with 11,800 employees worldwide, is part of RELX, a global provider of information-based analytics and decision tools for professional and business customers.
About Forrester Consulting
Forrester provides independent and objective research-based consulting to help leaders deliver key outcomes. Fueled by our customer-obsessed research, Forrester’s seasoned consultants partner with leaders to execute their specific priorities using a unique engagement model that ensures lasting impact. For more information, visit forrester.com/consulting.
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