Form IN01 UK: Register a Company at Companies House
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Setting up a limited company in the UK starts with one document in particular: Form IN01. It's the application you send to Companies House to bring a new company into legal existence, and it captures everything the registrar needs to know about your business on day one.
Getting it right matters, because the details you enter appear on the public register and shape how your company is run from the moment it's incorporated. On this page I'll walk through what Form IN01 actually asks for, who needs to sign it, how it connects to your articles and memorandum, and the practical points founders tend to trip over.
If you'd rather talk through your situation before you file, you can book a call with an experienced legal adviser at the bottom of the page.
What this document is
Form IN01 is the official application to incorporate a new company in the United Kingdom. It's the paper route into the company register maintained by Companies House, and it captures the foundational facts about the business you're creating. Most people never see the paper version because they incorporate online through the Companies House web service or a formation agent, but the underlying information required is the same whether you file digitally or on paper.
The form establishes the legal identity of your company: its proposed name, its type (private limited by shares is by far the most common), where it will be registered (England and Wales, Scotland, Wales, or Northern Ireland), and who the first officers and owners will be. It also captures information about people with significant control, the share structure if the company has one, and the registered office address that will serve as the company's official point of contact. Once Companies House accepts the application, they issue a certificate of incorporation and the company legally exists.
How to use this document
- Choose and check your company name. Before you touch the form, run your proposed name through the Companies House name availability checker. Names that are identical or too similar to an existing one will be rejected, and certain sensitive words need permission. Pick something you're confident you can live with long term.
- Decide your company type and structure. Most founders choose a private company limited by shares, but you might opt for limited by guarantee (common for social enterprises and clubs) or unlimited. Your choice affects how profits, liability, and ownership work, so think carefully before selecting a box on the form.
- Gather director, secretary, and PSC details. You'll need full names, dates of birth, nationalities, occupations, service addresses, and usual residential addresses for each director. If anyone holds more than 25% of shares or voting rights, or otherwise exercises significant control, they need to be listed as a person with significant control.
- Set out your share capital and shareholders. If your company is limited by shares, you'll record the number and class of shares being issued, the nominal value, and which subscribers are taking which shares on incorporation. Even a one-person company with a single £1 share needs this section completed accurately.
- File with Companies House and pay the fee. Submit the completed application along with your memorandum of association and either model articles or bespoke articles. Companies House charges a filing fee which varies depending on whether you file online or by post, so check gov.uk for the current amount before you send anything.
Common questions
If you're dealing with this kind of situation, speak to an experienced legal adviser who can walk you through it — from £89.
Common questions
Q Do I have to use Form IN01 if I incorporate online?
Not directly. When you incorporate through the Companies House online service or a formation agent, you fill in a web form that collects the same information Form IN01 asks for. The paper Form IN01 is used for postal applications and for unusual situations that can't be handled digitally, such as certain sensitive names or non-standard structures.
Q What's the difference between a registered office and a service address?
The registered office is the company's official address where statutory mail and legal notices are sent. A service address is the address given for each individual director or PSC to receive correspondence in their role. They can be the same, but many directors use a service address that isn't their home to keep their residential address off the public record.
Q Can I use the same address for multiple directors?
Yes. Several directors can share a service address, and the registered office can also double as a service address. Just remember that service addresses appear on the public register, so pick one you're comfortable being visible. Residential addresses are collected but generally kept off the public record unless you use them as your service address.
Q What are model articles and do I need to attach them?
Model articles are the default set of constitutional rules provided in legislation for standard private companies. If you don't supply your own articles, the relevant model articles apply automatically, so there's nothing to attach. Many founders adopt model articles to start and only draft bespoke articles when investors or specific share arrangements require them.
Q How long does Companies House take to process an IN01?
Online applications are typically processed within 24 hours, sometimes much faster. Postal applications using the paper Form IN01 take considerably longer, often a week or more, and same-day service is available at a premium. Processing times can vary with workload, so check the current service standards on gov.uk if timing matters.
Q What happens if I get something wrong on the form?
Companies House will reject applications that contain errors or missing information, and you'll usually need to correct and resubmit. Some mistakes can be fixed after incorporation by filing a separate form, such as changing a director's details or the registered office. Others, like an incorrect company name, may require a name change resolution and further filing.
Q Do I need a solicitor to file Form IN01?
No. Many founders file directly or use a formation agent, and for a straightforward company the process is designed to be accessible. That said, if your share structure is unusual, you have multiple founders with different rights, or you're unsure how to describe persons with significant control, a conversation with an experienced legal adviser before you file can save time later.
If you're dealing with this kind of situation, speak to an experienced legal adviser who can walk you through it — from £89.
Sources
This guide is based on primary UK law and official guidance.
- Guidance · UK GovForm IN01: Application to register a company (gov.uk)gov.uk
- Guidance · UK GovSet up a limited company: step by step (gov.uk)gov.uk
- Guidance · Companies HouseCompanies Housefind-and-update.company-information.service.gov.uk
- Guidance · UK GovPeople with significant control guidance (gov.uk)gov.uk
Legal helpline
Not sure you've got your IN01 right?
The details you put on Form IN01 shape your company from day one, from who controls it to how shares are held. An experienced legal adviser can help you think through the choices based on what you describe on the call, so you can file with confidence.
- Plain-English answers to your specific questions about registering your company
- Practical perspective on director, PSC, and shareholder details based on what you describe
- A clearer sense of whether model articles suit your situation
- Guidance on what to watch out for before you file with Companies House
Legal disclaimer
This article is for general information only. It is a tool to help you find your way — not legal advice, and not a substitute for speaking to a qualified adviser about your situation.