UK businesses and individuals with complex risks often use an insurance broker to access multiple insurers and arrange cover. This guide lists ten of the largest insurance brokers operating in the UK, ordered alphabetically, describing what each focuses on and how to verify any broker. The list reflects market scale, not an editorial ranking of quality. It uses the FCA Register, BIBA, and Money Helper guidance. Kael Tripton does not provide quotes, does not route enquiries to brokers, and does not earn commission from any firm mentioned.
Key Facts
- Insurance brokers are regulated by the Financial Conduct Authority and act as the agent of their client, accessing a range of insurers (FCA; BIBA, accessed June 2026).
- The UK general insurance broking sector is large, with the British Insurance Brokers' Association representing more than 1,800 regulated firms (BIBA, accessed June 2026).
- Brokers either give advice with a personal recommendation or arrange cover on a non-advised basis, checking it meets your demands and needs (FCA ICOBS, accessed June 2026).
- Using a broker can give access to dispute resolution through the Financial Ombudsman Service and, where eligible, the Financial Services Compensation Scheme (FCA; Money Helper, accessed June 2026).
- Every broker must be authorised by the FCA, which can be checked on the FCA Register at register.fca.org.uk (FCA, accessed June 2026).
What insurance brokers do in the UK
An insurance broker arranges insurance on behalf of a client, drawing on relationships with multiple insurers to place cover, including for hard-to-place risks. According to BIBA, brokers are the agent of their client and put the customer's interests first, which distinguishes them from insurers, who underwrite and manage the risk directly. The FCA regulates brokers under its Insurance Conduct of Business rules.
Brokers operate in two ways. Some give advice and a personal recommendation, assessing whether a policy is suitable for the client. Others arrange cover without a recommendation, checking only that the policy is consistent with the client's demands and needs and that the client is eligible to claim. Knowing which service a broker provides matters, because it changes the protection if something goes wrong.
The brokers below are among the largest operating in the UK, listed alphabetically. Scale rankings by revenue are published by industry bodies and trade reporting; this guide does not reproduce those figures or rank the firms by quality. Every firm should be checked on the FCA Register before any business is placed.
Providers compared at a glance
| Broker | Type | Typical focus | FCA reference |
|---|---|---|---|
| Aon UK Limited | Global broker | Corporate and commercial risk | Verify on FCA Register |
| Ardonagh Group | UK broking group | SME, personal and specialty | Verify on FCA Register |
| Arthur J. Gallagher | Global broker | Commercial and specialty | 311786 |
| Brown & Brown (UK) | Broking group | SME and specialty | Verify on FCA Register |
| Howden | UK and global broker | Commercial, personal, specialty | Verify on FCA Register |
| Jensten Insurance Brokers | UK broker | SME and commercial | Verify on FCA Register |
| Lockton Companies LLP | Global broker | Corporate and specialty | Verify on FCA Register |
| Marsh Limited | Global broker | Corporate and commercial risk | Verify on FCA Register |
| PIB Group | UK broking group | SME and specialty | Verify on FCA Register |
| WTW (Willis Towers Watson) | Global broker | Corporate and specialty | Verify on FCA Register |
FCA reference numbers should be confirmed on the Financial Conduct Authority Register, accessed June 2026. Large groups operate through several authorised legal entities, so check the specific entity arranging your cover.
Aon UK Limited
Who they are
Aon is one of the largest global insurance and reinsurance brokers, with a substantial UK presence operating through authorised entities including Aon UK Limited.
What they focus on
Aon concentrates on corporate and commercial risk, reinsurance, and employee benefits, typically serving larger organisations and complex programmes.
Who they suit
Medium and large organisations with complex or international risks that need broking and risk advisory services.
Ardonagh Group
Who they are
The Ardonagh Group is one of the largest UK-headquartered broking groups, operating through brands and authorised entities across advisory, specialty, and personal lines.
What they focus on
Ardonagh spans SME, personal, and specialty insurance through its various businesses, including well-known broking brands.
Who they suit
Individuals and businesses across the size range, depending on which Ardonagh brand and entity is involved.
Arthur J. Gallagher
Who they are
Arthur J. Gallagher Insurance Brokers Limited is authorised by the FCA under reference 311786 and is part of a global broking group with a large UK operation.
What they focus on
Gallagher arranges commercial, corporate, and specialty insurance, alongside risk management services.
Who they suit
SMEs through to large corporates seeking commercial and specialty cover from a global broker.
Brown & Brown (UK)
Who they are
Brown & Brown operates a significant UK broking presence built partly through acquisition, working through authorised UK entities.
What they focus on
The group focuses on SME and specialty insurance distribution across a range of trades and sectors.
Who they suit
Small and medium businesses and specialty risks served through the group's UK brands.
Howden
Who they are
Howden is a large UK-headquartered international broker that operates through entities including Howden Insurance Brokers Limited.
What they focus on
Howden arranges commercial, personal, and specialty insurance, and has expanded across the UK retail broking market.
Who they suit
Individuals and businesses across segments, from personal lines to corporate and specialty programmes.
Jensten Insurance Brokers
Who they are
Jensten is one of the larger independent UK broking groups, formed and expanded through consolidation of regional brokers and underwriting businesses.
What they focus on
Jensten focuses on SME and commercial insurance, with regional broking and niche schemes.
Who they suit
Small and medium businesses wanting a sizeable independent broker with regional reach.
Lockton Companies LLP
Who they are
Lockton is a large privately owned global broker with a UK operation arranging corporate and specialty insurance.
What they focus on
Lockton concentrates on corporate, commercial, and specialty risk, including international programmes.
Who they suit
Medium and large organisations seeking a privately owned global broker.
Marsh Limited
Who they are
Marsh is part of one of the largest global broking groups and operates in the UK through entities including Marsh Limited and Marsh commercial businesses.
What they focus on
Marsh focuses on corporate and commercial risk, with specialty and SME propositions across its UK businesses.
Who they suit
Businesses from SME through to large corporates needing broking and risk advice.
PIB Group
Who they are
PIB Group is a UK-headquartered broking group built through acquisition, operating across specialty and SME insurance.
What they focus on
PIB focuses on specialty lines, SME commercial insurance, and underwriting through its various businesses.
Who they suit
Businesses and specialty risks served through PIB's brands and schemes.
WTW (Willis Towers Watson)
Who they are
WTW is one of the largest global brokers and advisory firms, operating in the UK through authorised entities.
What they focus on
WTW arranges corporate and specialty insurance and provides risk and human capital advisory services.
Who they suit
Larger organisations and complex risks needing global broking and advisory capability.
How to compare insurance brokers objectively
Decide what you need first. For a straightforward risk, a smaller regional broker or a direct insurer may be enough, while complex, international, or hard-to-place risks may benefit from a larger broker with specialty teams. Bigger is not automatically better for a simple need.
Confirm how the broker is paid and whether it gives advice. Some brokers earn commission from insurers, some charge fees, and some do both. Ask whether you will receive a personal recommendation or a non-advised placement, as this affects your protection.
Verify the specific authorised entity on the FCA Register before placing business, because large groups operate through several firms. If something goes wrong, eligible complaints can be referred to the Financial Ombudsman Service, and the Financial Services Compensation Scheme may apply in some circumstances.
Frequently asked questions
What is the difference between an insurance broker and an insurer?
A broker arranges insurance on behalf of the client and can access multiple insurers, acting as the client's agent. An insurer underwrites and manages the risk directly. BIBA describes brokers as putting the customer's interests first.
Are insurance brokers regulated in the UK?
Yes. Insurance brokers are regulated by the Financial Conduct Authority. Regulation provides protections including access to the Financial Ombudsman Service and, where eligible, the Financial Services Compensation Scheme.
Do brokers always give advice?
No. Some brokers give advice with a personal recommendation, while others arrange cover on a non-advised basis, checking only that it meets your demands and needs. Ask which service you are receiving before buying.
How are insurance brokers paid?
Brokers may earn commission from insurers, charge the client a fee, or use a combination. You can ask a broker to explain how it is remunerated for arranging your cover.
How do I check an insurance broker is authorised?
Search the firm's name or reference number on the FCA Register at register.fca.org.uk. Large broking groups use several authorised entities, so confirm the specific firm arranging your cover.
Is a bigger broker always better?
Not necessarily. Larger brokers suit complex or international risks, while smaller brokers or direct insurers can be appropriate for straightforward needs. The right choice depends on the complexity of the risk and the service required.
Related Guides
Sources
- Why use a broker, British Insurance Brokers' Association, 2026
- General insurers and insurance intermediaries, FCA, 2026
- When to use an insurance broker, MoneyHelper, 2026
- The UK insurance market: the domestic market, HMRC, 2026
- Arthur J. Gallagher Insurance Brokers Limited, FCA Register, 2026
- Financial Ombudsman Service, 2026
Last reviewed: June 2026
