Choosing a UK Company Name

Most guides tell you to "search Companies House and see if the name is taken." That's step one of about six. This guide explains how Companies House actually decides whether your name is available — the normalisation rules, the restricted words, and the things that can go wrong after registration.

10 min read 8 sections

Introduction

Choosing a company name feels like the easy part of starting a business. In practice, getting it wrong can mean rejection at incorporation, a forced name change after registration, or a trademark dispute you didn't see coming. This guide explains how the rules actually work — and the things that trip people up.

If you just want to check name availability, you can do that right now — but reading this first will help you understand what the results actually mean.

The summarised checklist to pass before registering
Ends in "Limited" or "Ltd"?
Required for all private limited companies. Welsh equivalents accepted.
If no → application rejected
Only permitted characters? Under 160 chars?
Letters, numbers, and approved punctuation only. Nothing offensive.
If no → application rejected
Passes the "same as" normalisation check?
Name is stripped, uppercased, and compared against every name on the register.
If same → rejected, no appeal
Free of sensitive or restricted words?
100+ words require prior approval from specific bodies.
If restricted → need approval first, or rejected
No trademark conflicts?
Companies House doesn't check this — you must. Search the IPO register.
If infringes → legal action after registration
Not "too similar" to an active company?
Passing "same as" isn't enough. Could someone confuse you with them?
If too similar → forced name change within 12 months
Your name is clear
Register with confidence.

1. The rules: what Companies House will and won't accept

These are the non-negotiable requirements for any limited company name in England and Wales:

Required suffix

Every private limited company must end its name with "Limited" or "Ltd" (Welsh equivalents: "Cyfyngedig" or "Cyf"). No legal difference between the full word and the abbreviation. A rare exemption exists for companies limited by guarantee with charitable objects (s.60, Companies Act 2006).

Characters and length

Maximum 160 characters. Letters (A–Z), numbers (0–9), and a limited set of punctuation (hyphens, apostrophes, ampersands, etc.). Accented characters accepted since 2015. No offensive names — Companies House has broad discretion to reject.

Automatic rejections

A name is rejected if it normalises to the same string as an existing name (Section 2), contains a sensitive word without approval (Section 4), or is offensive.

2. How Companies House decides if a name is "the same as" another

Companies House doesn't do a literal string match. It applies normalisation rules that strip away superficial differences before comparing — two names that look different to you can be legally identical. Here's what gets normalised:

RuleWhat happensExample
Legal suffixes Limited, Ltd, PLC, LLP, Unlimited, and their Welsh equivalents are all stripped before comparison "Acme Limited" = "Acme Ltd"
Case All names are compared in uppercase — case is completely ignored "acme" = "ACME" = "Acme"
Punctuation All punctuation marks are removed — hyphens, apostrophes, full stops, commas, everything "O'Brien's" = "OBriens"
Spacing All whitespace is collapsed — extra spaces, different spacing patterns are ignored "Made Simple" = "MadeSimple"
& vs "and" The ampersand (&) and the word "and" are treated as identical "Smith & Sons" = "Smith and Sons"
Currency Currency symbols and their English word equivalents are treated as the same "£100 Club" = "100 Pound Club"
Accents Accented characters are normalised to their unaccented equivalents "Éco" = "Eco"
Leading "The" "The" at the start of a name is disregarded "The Acme Group" = "Acme Group"

The effect is that two names which look different on paper can resolve to the same normalised form — and if they do, the new name is rejected. This is an automatic, non-discretionary check. There is no appeal process for a "same as" rejection; the name simply cannot be registered.

Worked examples

Here are some pairs of names that would be treated as "the same" after normalisation:

Example Company name Normalised Result
Punctuation and suffix Smith-Jones Consulting Limited SMITHJONESCONSULTING Same — rejected
SmithJones Consulting Ltd SMITHJONESCONSULTING
Ampersand vs "and" Brooks & Harper Ltd BROOKSANDHARPER Same — rejected
Brooks and Harper Limited BROOKSANDHARPER
Different enough Greenfield Solutions Ltd GREENFIELDSOLUTIONS Different — allowed
Green Field Consulting Ltd GREENFIELDCONSULTING
Important: Passing the "same as" check only means your name isn't identical to an existing one after normalisation. It doesn't mean you're in the clear — you can still face a "too similar" challenge after registration. See the next section.

3. "Same as" vs "too similar" — two different problems

A name can pass one check and fail the other — they're completely different mechanisms:

"Same as" (s.66)"Too similar" (s.67)
When it happens At incorporation — automatic check before your company is registered After registration — direction must be issued within 12 months of incorporation (s.68)
Who decides Automated system — applies the normalisation rules mechanically Secretary of State (in practice, Companies House) — discretionary judgment
The test Do the two names produce the same normalised string? If yes, rejected. Is the name similar enough to cause confusion with an existing company? Subjective assessment.
Result if triggered Application rejected — the company is not registered at all Direction to change your name — the company exists but must adopt a new name within a specified period
Can you appeal? No — it's a hard rule. Choose a different name. Yes — you can object to the direction. If you don't comply, it's a criminal offence.

The "too similar" power is most commonly triggered by an existing company objecting. Factors considered include how close the names look and sound, whether the businesses are in the same industry, and whether there's a realistic risk of confusion. There's also a Company Names Tribunal (s.69) for cases involving goodwill, and since ECCTA 2023, Companies House has expanded powers to reject names intended to facilitate fraud or mislead.

The practical takeaway: don't rely solely on passing the automated check. Search the register yourself and consider whether your name could be confused with any active company in the same industry. Passing "same as" means you can register. It doesn't mean you'll keep it.

4. Sensitive and restricted words — the full list

Certain words require prior approval before use. Some are obvious ("Royal," "Bank"), but others — like "Group," "Foundation," or "Trust" — catch people off guard. If your name contains any of these, Companies House will reject your application without the right approval.

Words implying authority or status

Approval required from the Secretary of State. You'll need evidence justifying the use.

Word / ExpressionWhy it's restrictedApproval body
Association Implies an official representative body Secretary of State
Authority Implies governmental authority Secretary of State
Board Implies an official governing body Secretary of State
Charter / Chartered Implies a Royal Charter connection Privy Council
Council Implies a local authority or governing body Relevant government department
Foundation Implies a pool of money or regular source of finance for charitable purposes Secretary of State
Institute / Institution Implies an established learned or professional body Secretary of State
National Implies national scope or government connection Secretary of State
Register / Registered Implies an official registry Secretary of State
Society Implies a specific legal structure (e.g. building society) Secretary of State
Trust Implies a trust structure or charitable status Secretary of State

Words implying government or state connection

British · Britain · England · English · Scotland · Scottish · Wales · Welsh · Government · Parliament · Commission · Municipal · Police · Post Office

Approval comes from the relevant government department — Scottish Ministers for "Scotland"/"Scottish," Welsh Ministers for "Wales"/"Welsh."

Words implying royal connection

Crown · King · Queen · Prince · Princess · Royal · Royalty

Require government or Privy Council approval. Very rarely granted for commercial companies.

Regulated profession words

These indicate regulated activities — using them without the appropriate professional standing is potentially a criminal offence, not just a naming issue.

WordApproval body
ArchitectArchitects Registration Board (ARB)
Bank / BankingFCA / PRA
Insurance / Insurer / AssuranceFCA / PRA
DentalGeneral Dental Council
Medical / SurgeonGeneral Medical Council
Nurse / NursingNursing and Midwifery Council (NMC)
PharmacyGeneral Pharmaceutical Council (GPhC)
SolicitorLaw Society / Solicitors Regulation Authority
VeterinaryRoyal College of Veterinary Surgeons (RCVS)
PatentChartered Institute of Patent Attorneys (CIPA)

Financial and charitable terms

Benevolent · Charity · Charitable · Co-operative · Credit Union · Friendly Society · Fund Management · Trade Union · University

"University" requires Privy Council approval. "Charity"/"Charitable" require Charity Commission approval with evidence of genuine charitable purposes.

This list is not exhaustive. The Regulations contain over 100 entries. We've covered the most commonly encountered words here. The full list is published by Companies House across three annexes in their incorporation and names guidance. If you're unsure about a word in your proposed name, check before applying — a rejected application wastes time and may delay your incorporation.

5. What about dissolved companies?

Generally, yes — once dissolved, a company's name drops off the active index and can be re-used. But there's a catch: dissolved companies can be restored to the register within 6 years (via administrative restoration under s.1024 or court order under s.1029). If that happens, the restored company has priority and you'll be directed to change your name.

The risk depends on how recently the company was dissolved and how active it was:

Risk level Situation
Lower Dissolved more than 6 years ago (outside the restoration window for most purposes). The name is generally safe to use.
Moderate Dissolved 2–6 years ago, with minimal filing history or apparent activity. Probably fine, but there's a non-zero chance of restoration.
Higher Dissolved within the last 1–2 years, especially if the company had active trade, employees, or assets. Consider choosing a different name or at least doing additional due diligence.
Our name checker flags this for you. When you search a name and it matches a dissolved company, we show you the dissolution date and company status so you can assess the risk yourself. Try it here →

6. Trademarks — the risk Companies House doesn't check for

This is arguably the biggest gap in the company naming process: Companies House and the Intellectual Property Office (IPO) don't talk to each other. You can register a company name at Companies House that directly infringes someone's registered trademark, and Companies House will accept it without question. The two systems are completely separate.

This means passing the Companies House name check gives you no protection against a trademark claim. A company with a registered trademark can take legal action against you for using a name that infringes their mark, regardless of when you incorporated.

What to check

Before committing to a name, search the IPO trademark register at gov.uk/search-for-trademark. This is a free search. Look for trademarks that are identical or very similar to your proposed name, particularly those registered in the same class of goods or services as your business.

Also check the EU trademark register (EUIPO) if you'll trade in Europe. Bear in mind that unregistered rights ("passing off") can also apply — businesses that have built goodwill in a name can challenge you even without a formal trademark.

When in doubt, ask a trademark attorney. A short consultation costs far less than rebranding after a cease-and-desist.

7. Practical tips for choosing a name that sticks

The sections above cover the legal framework. These are practical recommendations informed by experience.

  • Check domain availability early. Your company name and domain don't have to match, but it helps. Check .co.uk and .com before committing.
  • Say it out loud. If you regularly give your name over the phone (to banks, HMRC, clients), test whether people can hear it and spell it. "Kopykat Kreative Ltd" is a headache at every call centre.
  • Test it with "Ltd" appended. Your name appears with the suffix on invoices, contracts, and bank statements. Some brand names become awkward with "Limited" tacked on.
  • Avoid names that box you in. "Manchester Web Design Ltd" works until you expand to other cities or services. A less literal name gives you room to grow.
  • Skip "Group" or "Holdings" unless you mean it. "Group" implies subsidiaries. On a single-entity business it looks pretentious and may trigger sensitive-word scrutiny.
  • Don't echo well-known brands. Even without a formal trademark conflict, obviously derivative names ("Amazonia Logistics Ltd") invite cease-and-desist letters from companies with deep pockets.

8. Check your name now

Now that you understand the rules, run your proposed name through our free checker. It searches the live Companies House register, applies the same normalisation rules described above, flags sensitive words, and shows you similar active and dissolved companies — so you can assess availability properly before applying. Once your name is sorted, our company formation checklist walks you through everything else you need to do to incorporate.

Ready to check your company name?
Our free name checker searches the Companies House register, applies the official normalisation rules, and flags sensitive words — all in one search.
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