Russell Cooke Bedford Row Holborn

About Katie

My role is to help people navigate what can be one of the most difficult times of their lives. I understand both the emotional and legal issues involved when a relationship breaks down and use my professional skills with my considerate but determined approach to get matters resolved in the best way possible.

Katie advises across the full breadth of family law with many of her cases involving an international element. She is a Resolution trained family mediator in financial and private law children matters.

Her specialist acumen is in cases involving international child relocation and disputes involving child arrangements. She advises on divorce, relationship breakdown and managing the associated financial matters. She also assists with the drafting of nuptial agreements. Her clients range from HNW individuals, international entrepreneurs and families of inherited wealth. 

Katie is ranked in Chambers HNW 2023 (Band 5 for Family/Matrimonial Finance: High Net Worth - London) as well as a Recommended Lawyer in Legal 500 2024.

She is incredibly knowledgeable and strategic but also very human in the way she dealt with our matters. She understands the family court system intrinsically and applies common sense to situations.
Chambers HNW (2025)

Education

  • Read History at King’s College London, 2000-2003
  • Completed the General Diploma in Law (GDL) at the College of Law, London, 2003-2005
Katie is passionate about all her clients, capable, unflappable and very well respected by her peers.
The Legal 500 (2025)

Experience

Katie qualified in 2007, joining the boutique family law firm Alexiou Fisher Philipps as a solicitor in 2011, later becoming a partner at the firm in 2016.

She has been involved in the following notable cases: 

  • Re L (Residence: Jurisdiction), the Court of Appeal case W (Children) on relocation
  • the influential High Court decision JKN v JCN addressing the jurisdiction of a transatlantic divorce
Katie Longmate has cemented herself in the mediation world. A super human touch regularly helps clients reach successful outcomes.
The Legal 500 (2025)

Memberships

Katie is a:

  • member of Resolution and its Wellbeing Committee

Katie's highlights

News

09.07.2025

Is my estranged husband lying about his assets?—Financial Times

Partner Katie Longmate has responded to a reader’s question in the Financial Times Money Clinic column about concerns that an estranged husband may be...
Family and children partner - Katie Longmate | Russell-Cooke
Katie Longmate
1 min Read
News

01.07.2025

Four Russell-Cooke partners listed in the Spear's Family Lawyers Index 2025

Russell-Cooke is delighted to announce that four partners have been featured in Spear's Family Law Index 2025, which lists the leading family lawyers for high-net-worth clients...
James Carroll, Managing Partner in the Russell-Cooke Solicitors, family and children team. Kate Hamilton, Partner in the Russell-Cooke Solicitors, family and children team. Fiona Read, Consultant in the Russell-Cooke Solicitors, family team Family and children partner - Katie Longmate | Russell-Cooke
Multiple Authors
1 min Read
James Carroll, Kate Hamilton, Fiona Read, Katie Longmate
News

29.04.2025

Family and criminal law: when two legal systems meet

It is not uncommon for someone in the middle of family proceedings to find themselves in need of help from the police or advice from a criminal lawyer, or vice...
Family and children partner - Katie Longmate | Russell-Cooke
Katie Longmate
3 min Read
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