• Wellesley College, B.A. (2003) cum laude
  • Cornell Law School, J.D. (2011)


  • New Jersey
  • New York
  • U.S. District Court, Southern District of New York
  • U.S. District Court, Eastern District of New York
  • U.S. District Court, District of New Jersey
  • U.S. District Court, Eastern District of Michigan
  • U.S. Court of Appeals, Seventh Circuit
  • U.S. Court of Appeals, Fourth Circuit

Honor Costello


Honor Costello is a partner in Crowell & Moring's New York office. Her practice focuses on litigating complex health care, antitrust, intellectual property, and commercial disputes, including class actions and multidistrict litigation (MDL) proceedings. She has represented insurers, reinsurers, managed care organizations, financial institutions, manufacturers, energy companies, and pharmaceutical companies in state and federal litigations.

While in law school, she served as a managing editor of the Cornell Journal of Law and Public Policy. She also served as a judicial intern to the Honorable Charles J. Siragusa, U.S. District Court for the Western District of New York. 

Representative Matters

  • Defending health insurance companies in nationwide and statewide class actions asserting antitrust claims.
  • Representing major automobile manufacturer in nationwide class action alleging vehicle performance defects, breach of warranty, fraud, and consumer protection claims.
  • Representing a medical school in litigation relating to breach of a patent license agreement.
  • Defending health insurers in Employee Retirement Income Security Act (ERISA) litigation.
  • Representing a U.S. reinsurance company in litigations relating to underlying asbestos and environmental losses.
  • Representing a leading marketing and communications agency in a dispute with former employees regarding violation of nonsolicitation covenants and misappropriation of trade secrets.

Speeches & Presentations

  • "Critical Junctures: Depositions of Class Representatives and Challenging Expert Testimony at the Class Certification Stage," New York State Bar Association Annual Meeting 2019 – Torts, Insurance and Compensation Law and Trial Lawyers Sections (January 17, 2019). Panelists: Honor Costello and Jacqueline K. Seidel.


Firm News & Announcements

June 16, 2021 Civil Rights Groups Achieve Voting Rights Victory in Louisiana
January 3, 2019 Crowell & Moring Elects Eight New Partners and Promotes 21 Associates to Counsel
January 9, 2017 Crowell & Moring Elects Six New Partners and Promotes 19 Associates to Counsel
November 7, 2016 Legal Aid Society Honors Crowell & Moring Attorneys for Protecting the Rights of Low Income Workers