Register a Limited Company with HMRC (and Companies House): Step‑by‑Step Guide

Key Takeaways

• You must register your limited company with Companies House first, then register for corporation tax with HMRC within 3 months of starting any business activity such as trading, advertising, or employing staff.

• Each director must verify their identity through GOV.UK One Login and obtain a unique personal code before you can register your company online with Companies House.

• During incorporation, you need to choose an available company name, list all people with significant control, provide a registered office address, and include at least one director.

• Once the company legally exists, you must keep accounting records, file annual accounts and Company Tax Returns, and pay corporation tax on profits by the relevant deadlines.

• If your company is not trading (dormant), you still need to file confirmation statements and dormant accounts with Companies House, and you must inform HMRC that the company is dormant to avoid Corporation Tax obligations.

Introduction: HMRC vs Companies House – Who You Register With and When

Setting up a UK limited company involves dealing with two separate government bodies, each with a different role. Companies House handles incorporation - it creates the company, assigns a company number, and maintains the public register. HMRC deals with tax - it collects corporation tax, manages PAYE, and handles VAT.

You cannot register for corporation tax until the company legally exists on the Companies House company register. These two registrations happen in sequence, not at the same time.

Here is the typical order of the process:

• Choose your structure - decide between sole trader, limited company, or another form

• Incorporate with Companies House - submit your details, pay the fee, receive your certificate of incorporation

• Register with HMRC - register for corporation tax within 3 months of starting business activity

• Open a business bank account - separate your company finances from personal money

This guide covers the England and Wales process for the 2026 tax year. Scotland and Northern Ireland follow a largely similar process, with only minor differences in address jurisdiction rules.

Decide if a Limited Company Is Right for You

Before you register, you need to decide whether a limited company is the right structure for your business. A sole trader operates as an individual - you and the business are the same legal entity, and you are personally liable for all debts. A limited company is legally separate from its owners, which means it offers limited liability protection.

Most small businesses start as either sole traders or limited companies. Your choice affects how you pay tax, your legal exposure, and the amount of admin you take on.

A sole trader structure may suit you better if:

• You run a very small side business with low income

• Your work carries low financial risk

• You want straightforward finances and minimal paperwork

A limited company can be preferable when:

• You do higher risk work or have significant contracts

• You have multiple owners or shareholders expecting dividends

• Clients or suppliers require you to operate as a company

• You plan to attract investments or outside capital

Limited liability means the company is a separate legal person. If the company runs into debt, the owners generally only lose what they put in - their share capital - rather than their personal property or savings. A sole trader, on the other hand, is personally liable for every business debt.

You can start trading as a sole trader and later incorporate a limited company. However, transferring contracts, assets, and bank accounts takes planning and preparation, so it is worth thinking about this before you begin.

Check and Choose Your Company Name

Your company name must follow Companies House rules, and it must be unique on the companies register. Before you submit anything, check company name availability using the Companies House name availability checker to confirm your chosen name is not already taken.

A few rules to keep in mind:

• Your company name should reflect your products or services where possible

• Ensure your company name is consistent in all documents - the incorporation form, tax registration, and your business bank account should all match exactly

• Avoid using sensitive words such as "Royal", "Authority", or "Chartered" unless you have the required consent or supporting documents

• The registered name must end with "Limited" or "Ltd" (or Welsh equivalents)

Your company's registered name can differ from any trading name you use day-to-day. However, the registered name must appear on official documents, invoices, and your website. Inconsistencies between your registered name and the name you use elsewhere can cause delays in registration or problems opening a business account.

Get Ready: What You Need Before You Register Your Company

Collecting your details in advance speeds up the online registration with Companies House and later with HMRC. Scrambling for information mid-application leads to errors and wasted time.

Here is what you need to gather:

• Proposed company name - already checked for availability

• Registered office address - you must have a registered office address in the UK for official correspondence. This must be a physical address in the jurisdiction of incorporation. It can be a home address, an accountant's office, or a virtual office, but not a PO box

• Director details - at least one director must be appointed to register a limited company in the UK. Provide full names of all individuals on the application (forenames in full, not initials), date of birth, nationality, and service address

• Shareholder details - names and addresses of subscribers, plus the number and nominal value of shares they hold

• People with significant control (PSC) - identifying people with significant control is required during registration for a limited company. A PSC is usually someone holding more than 25% of shares or voting rights. Their details must be recorded on the PSC register

• Share structure - decide how many shares, what classes, and nominal value. For example, a simple setup might be 1 ordinary share of £1. This affects ownership and future dividends

• SIC code - each limited company must have a Standard Industrial Classification code to describe its business activities

Verify Directors’ Identities Before Registration

Since 18 November 2025, every director setting up or managing a limited company must verify their identity before filing with Companies House. You may need to verify your identity using GOV.UK One Login, which is the government's standard route for identity checks.

Each director must have a unique personal code for verification. This code is issued after successful identity verification and is tied to the individual, not the company. Here is what you need to know:

• What the personal code is - a unique alphanumeric code issued to each person after identity verification. You need a unique personal code to verify your identity for any company filings

• Where it appears - your personal code can be found in your Companies House account under your profile

• Why it must be kept secure - the code is used in incorporation forms, director appointments, and confirmation statements. If it falls into the wrong hands, someone could make filings on your behalf

You only need to verify your identity once for Companies House. Once verified, your personal code can be reused for future company appointments or when setting up new companies. If a director has not yet verified, they will be directed through the online identity check process before they can complete the incorporation.

Register Your Limited Company with Companies House

This is the legal incorporation step - the moment you create the company with Companies House. Until this is done, no HMRC registration is possible.

There are three main ways to register:

The standard fee for online registration with Companies House is £100 (as of 1 February 2026). Register by post using form IN01 for £124. Online applications are processed within 24 hours in straightforward cases, while postal applications take considerably longer.

The incorporation form requires:

• Company name and registered office address

• Director details (full legal names, not initials)

• Shareholder (subscriber) details and share capital

• People with significant control

• Articles of association - many small companies use model articles unless they need bespoke rules

Ensure the memorandum of association is included with IN01, as it is a core document confirming the subscribers' intention to form the company. Once the application is accepted, a Certificate of Incorporation is issued after successful registration, proving the company's legal existence. This certificate contains your company number and official date of incorporation.

Register for Corporation Tax with HMRC

Once your company legally exists, you need to register for corporation tax. It is essential to notify HMRC of business activities within three months of starting - not from the date of incorporation, but from when you actually start trading, advertising, or employing staff.

To register, you must set up a Government Gateway account for HMRC services. A Government Gateway account is necessary to file taxes and manage company information online. Once you have your government gateway user ID, log in and add the company to your business tax account.

You can register for corporation tax online or by post. During registration, you will need:

• Your company registration number (from the certificate of incorporation)

• The date you started trading

• Your main business activity code (SIC code)

• Your company's registered office address

• Your accounting reference date

After registration, Companies House will send a Unique Taxpayer Reference (UTR) letter to the registered office. You need a Unique Taxpayer Reference for registration with HMRC's online services. HMRC sends an Activation Code within seven days of verification, which you use to activate your online tax account.

Register for corporation tax within 3 months of trading to avoid penalties. The corporation tax accounting period normally aligns with the company's financial year, and corporation tax is payable 9 months and 1 day after the end of each accounting period.

Set Up a Business Bank Account and Separate Your Finances

A business bank account must be established to manage a company's financial transactions. While not always an explicit legal requirement, a limited company is a legally separate entity from its owners, which means mixing personal and company money creates serious problems.

Benefits of a dedicated bank account:

• Clear separation of personal and company money

• Easier bookkeeping for corporation tax and VAT

• Simpler audit trail for expenses and income

• More professional image when dealing with clients and suppliers

Banks typically ask for the certificate of incorporation, company number, photo ID and proof of address for each director, plus details of people with significant control. Double check that names and addresses match your Companies House records exactly - some banks refuse applications where details do not align.

Online-only banks and high street banks offer different features and fee structures. Some charge monthly fees, others are free for a set period. Compare options before committing so you can manage your finances effectively from day one.

Meet Your Ongoing HMRC and Companies House Responsibilities

Registering the company is only the beginning. Directors have continuing legal and tax responsibilities that run for as long as the company exists.

HMRC obligations:

• File Company Tax Returns (CT600) within 12 months of your accounting period end

• Pay corporation tax on profits - active companies pay corporation tax 9 months and 1 day after the accounting period ends

• Operate PAYE if employing staff or paying a salary to directors

• Register for VAT if annual turnover exceeds the threshold

• Keep accurate records of all income, expenses, and payroll

Companies House obligations:

• File annual accounts (first set due 21 months after incorporation, then 9 months after each accounting reference date)

• Submit a confirmation statement each year to confirm directors, shareholders, people with significant control, and registered office address

• Notify Companies House of any changes to directors, registered office, or share structure

Directors must keep accurate accounting records for at least 6 years. This includes invoices, bank statements, expenses, payroll records, and board minutes.

If your company is not trading, it can remain dormant. But directors must still file minimal accounts and confirmation statements with Companies House. You must inform HMRC if your company becomes dormant so it does not expect corporation tax returns.

Common Mistakes When Registering a Limited Company

Many incorporation applications are rejected or delayed for avoidable reasons. Here are the most frequent errors:

• Inconsistent company names - entering different versions of the name across forms, or using a trading name instead of the registered name

• Incorrect or missing PSC information - failing to identify all people with significant control, or submitting wrong details

• Incomplete memorandum of association - not including all required subscribers or signatures

• Using initials instead of full legal names - provide full names of all individuals on the application, as Companies House will reject forms with initials only

• Nationality mistakes - entering ethnicity or place of birth instead of country of nationality, or spelling errors that trigger queries

• Incorrect subscriber details - ensuring the company is not listed as subscribing to itself, and that any corporate subscribers have evidence of legal personality

Filing online with built-in validation catches many of these errors before submission. Always double check every detail before you submit to significantly reduce the risk of rejection.

What Happens After You Register: First Tax Year Timeline

Here is the typical journey from incorporation through the first financial year:

1. Day 1 - Receive certificate of incorporation and company number. The company legally exists

2. Shortly after - HMRC sends a UTR letter to your registered office

3. Within 3 months of business activity - Register for corporation tax

4. Start trading - Begin keeping records from day one. You can start trading straight away after incorporation

5. Throughout the year - Maintain accounting records for all transactions, income, and expenses

After the first accounting period ends:

• You have 9 months and 1 day to pay any corporation tax due

• You have 12 months to file the Company Tax Return (CT600)

• Companies House expects first accounts within 21 months of incorporation - missing this triggers automatic penalties ranging from £150 to £1,500

As an example, if you incorporate on 11 May, your default accounting reference date is 31 May the following year. Your first accounts would cover the period from incorporation to that date.

One point that catches many new directors: the tax year for individuals runs 6 April to 5 April, while a company's accounting period can be any 12-month period. This means dividends and director salary may span different personal tax years for HMRC purposes, so planning around these dates matters.

Further Information and Where to Get Help

Government guidance changes periodically, so always confirm the latest rules before you act. Here are the key resources:

• GOV.UK - search for "Set up a private limited company" for the most current step-by-step guide

• Companies House guidance - covers incorporation, company names, accounts filing, and identity verification rules

• HMRC Corporation Tax manuals - detail deadlines, registration, and obligations for small companies

Professional advisers - such as an accountant or business adviser - can support you in choosing between sole trader and limited company, setting up bookkeeping, and handling HMRC registrations. If your circumstances are complex (for example, multiple shareholders, overseas directors, or bespoke articles of association), professional advice is particularly valuable.

Keep copies of all correspondence from Companies House and HMRC in one secure place. This includes your certificate of incorporation, UTR letter, activation codes, and any notice of changes filed.

If you plan to operate in a regulated sector - for example, financial services, healthcare, or property management in certain country jurisdictions - you may need extra licences or approvals beyond Companies House and HMRC registration. Check before you create the company to avoid wasted cost and effort.

FAQ

Do I register with Companies House or HMRC first?

You must register your company with Companies House first to obtain a company number and certificate of incorporation. Only once the company legally exists can you register it with HMRC for corporation tax. HMRC will usually write to the company's registered office shortly after incorporation, but you are responsible for making sure registration is completed within 3 months of starting to trade.

Can I trade before registering for Corporation Tax?

Yes. You can start trading as soon as the company is incorporated. However, you must register for corporation tax with HMRC within 3 months of beginning any trading or business activity. Failing to register on time can lead to penalties and interest, even if your company makes little or no profit in the first year.

What if my company is not trading (dormant)?

A dormant company has no significant transactions and is not actively doing business. It normally does not need to file corporation tax returns, but directors must inform HMRC that the company is dormant. You still need to file annual confirmation statements and dormant accounts with Companies House until trading begins or the company is closed.

Do I need a business bank account in the company’s name?

While the law does not always explicitly force a separate bank account, in practice a limited company should have its own business account in the company name because it is a legally separate entity. Using a personal bank account for company income and expenses blurs the separation between owner and company, making accounting and corporation tax compliance much more difficult.

Can I change from a sole trader to a limited company later?

Yes, you can switch from sole trader to limited company at any time by incorporating a company and registering it with HMRC for corporation tax. Practical steps include informing clients of the change, opening a company bank account, transferring assets and contracts where appropriate, and registering the director for PAYE if taking a salary. You should also suggest to your accountant that they review any tax implications of the transfer before you complete the process.