Skip to Main Content

Cost-Effective Electronic Legal Research: Lexis & Westlaw Compared


Humorous video from Columbia Law School comparing Westlaw, Lexis and Bloomberg Law

Similarities of Lexis Advance and Westlaw

Similarities of Lexis Advance (for Law Schools) and Westlaw include:

  • All in one search box – can pull up a case, KeyCite®/shepardize, search everything on the system at once
  • Enhanced Natural language searching (called WestSearch in Westlaw, it is completely different from the classic natural language searching)
  • Folders
  • Segment searching now available for Lexis Advance.  Field searches  work on Westlaw.

Other LibGuides


Basic Differences Between Lexis Advance and Westlaw

The main differences are:

  1. Natural language algorithms appear to be based on different criteria, so may give different results.
  2. Both systems allow terms and connectors searching.  Westlaw also provides Additional Relevant Westsearch cases using the Westsearch algorithm, in addition to your terms and connectors results.
  3. Westlaw has the Key Number Outline and ability to search by key number.  Lexis Advance ties case headnotes into a new Topic Index.  One can get topic documents, create an alert or view topics in an index. 
  4. Lexis Advance has a Wordwheel which offers suggested terms while you are typing.  Westlaw will suggest databases and specific publications you may be looking for.
  5. Post -Filters vary based on content on both systems.  Just some of the unique postfilters include: Lexis Advance has postfilters for keyword (from a list - uses CoreTerms), most cited (from list).  Westlaw has a postfilter for key number, viewed in the last 30 days, documents in folders and for statute title.  Westlaw also allows you to filter for a particular court, for example, Ohio Eighth District, whereas Lexis Advance only filters for court level - ie. appellate courts.  You can add segment search terms such as court(eighth) in Lexis Advance.
  6. Lexis Advance includes results from the web in a separate tab.
  7. Each systems offers some unique ways of sorting results, for example most cited and most used in Westlaw, Table of Contents for statutes in Westlaw,  document title in Lexis Advance, content type or agency in Lexis Advance.  Ways of sorting results vary by content type (cases, statutes, administrative, etc.) in both systems.
  8. Lexis Advance has a Legal Issue Trail.
  9. Innovations Research Map in Lexis Advance is a graphical representation of the steps in each of your searches. It shows the number of results found in each content type, the filters you applied, filters you removed, documents you delivered, Shepardize, or saved to a work folder, and other activities.  You can select a document in a research map and find similar documents. There is also a Compare Search Results tab to find commonalities among searches.
  10. Shepard’s Graphical in Lexis Advance – a graphical map showing the history of subsequent citing cases, as well as subsequent direct history so you can easily see whether a case has been overruled.  Lexis Advance also has a Citing Decisions Grid showing a graphical representation of the number citing cases by court by analysis (positive, negative, etc.) and by year by analysis.  Westlaw has graphical history of a case. 
  11. For statutory code sections, Westlaw has a Graphical Statute history and legislative history documents linked conveniently from the history tab.
  12. Customers can work with their sales representatives on pricing for Westlaw subscriptions.  95% of Lexis subscribers to Lexis can get Lexis Advance for no additional cost.  Both systems do not charge for searches or for accessing documents within your plan.  There is a charge for retrieving a document outside of your plan in both systems.
  13. Westlaw has more citation formats available for copying and pasting.  Westlaw has Bluebook brief and law review format, and numerous state citation formats, including Ohio.   Lexis Advance will add more, but currently they have Bluebook brief and California formats.