UK Company Name Rules

Before registering a new company — or buying a pre-registered name — it's worth understanding the rules that govern what a UK company name can and cannot be. These rules are set out in the Companies Act 2006 and associated regulations.

The Basics: What Must Every Company Name Include?

All private limited companies registered in England, Wales, or Scotland must end with one of the following:

• Limited (in full)
• Ltd (the accepted abbreviation)

Companies registered in Wales may alternatively use the Welsh equivalents: Cyfyngedig or Cyf.

Public Limited Companies must end with Public Limited Company or PLC. This guide focuses on private limited companies (Ltd).

Permitted Characters

A UK company name may only contain the following characters:

The "Same As" Rule

Companies House will not register a company name that is the same as an existing company on the register. When checking for sameness, Companies House applies a set of rules that effectively ignore:

• Differences in case (upper vs lower)
• The presence or absence of certain articles: the, a, an
• Certain common corporate abbreviations: co, company, & vs and
• Punctuation differences (a hyphen vs a space, for example)
• The suffix: Limited, Ltd, PLC etc.

This means that if Acme Trading Ltd is registered, Companies House will also block The Acme Trading Company Limited and Acme-Trading Ltd.

Sensitive Words and Expressions

Some words and expressions require prior approval from Companies House (and sometimes from a relevant government body) before they can be used in a company name. These are known as sensitive words. Examples include:

Prohibited Names

Companies House will outright reject names that:

• Are offensive or contain obscene language
• Imply a connection with a government department or agency (e.g. using HMRC or NHS)
• Would constitute a criminal offence (e.g. implying illegal activity)
• Are identical to an existing company under the same-as rules

Trademarks Are Separate

An important point: Companies House registration does not grant trademark rights. A company can be registered with a name that is already trademarked by another party — and the trademark owner can still take legal action over its use.

If you are buying a company name for commercial use, it's worth checking the UK Intellectual Property Office trade mark register to ensure the name does not infringe on an existing trade mark.

Why Short Names Are So Valuable

Given the "same as" rules, it becomes clear why very short company names — particularly single letter and double letter names — are so rare and valuable. A single letter Ltd blocks a vast number of potential new registrations, making these names extraordinarily difficult to obtain through standard registration channels.

The only practical way to acquire a short company name that is already registered is to purchase it from the current owner — exactly what we facilitate.