Getting ready to file company accounts by software: your authentication code and presenter account

acrenvo.com/guides/getting-ready-to-file-company-accounts-by-software, last reviewed 1 November 2026

Priya is fictional. She is the only director of a small limited company, and every year she has filed its accounts herself on the Companies House website. She knows the website will stop taking accounts in April 2028, and she would rather sort out the setup early than find a missing code a week before her deadline. This guide walks through what Companies House says a company needs before it can file through software, in the order Priya would tackle it.

What changes for a company that files on the website

Companies House’s rule covers every company, including one whose director files without an accountant. From 1 April 2028, all companies must file their accounts using commercial software. This applies to companies who file accounts themselves, and companies who use a professional (such as an accountant) to file their accounts.

The guide to company accounts by software only explains the change itself. This guide is about the practical setup, because software alone is not enough: Companies House also needs to know who is sending the accounts and that the company has agreed to it. To file company documents using software, you’ll need:

• your company authentication code
• to apply for a presenter account - you’ll get a presenter ID and code
• to apply for a Companies House credit account (if you need to file documents with a fee)

Your company authentication code

The authentication code is the piece most directors already have, even if they have not thought about it since they last filed. The company authentication code is a 6 digit alphanumeric code issued by Companies House to each company. The code is used to authorise information filed online and is the equivalent of a company officer’s signature. You’ll need a company authentication code to file your information online or file using commercial software.

The same code carries across from the website to software, so Priya does not need a new one for the move. You’ll use the same company authentication code for your company to file online using:

• Companies House WebFiling
• Find and update company information
• commercial software

It is easy to mix this code up with the newer one that directors get from identity checks, so Companies House spells out the difference. The company authentication code is different to the Companies House personal code which is issued to individuals when they verify their identity. The guide to Companies House identity verification explains the personal code.

Requesting the code, or a reminder of it

If Priya cannot find the code, she can ask for it again, but it comes by post, so the timing matters. To request a code, you’ll need to create an account or sign in to Companies House WebFiling and follow the steps. We’ll send your code by post to your company’s registered office - it can take up to 10 working days to arrive. If your company already has a code, we’ll send you a reminder.

If you cannot access your company’s registered office address, we can send your authentication code to your home address instead. There is no faster route, because Companies House will not give the code out any other way. We cannot send your company authentication code by email or tell you the code over the phone.

Setting up a presenter account

The presenter account is the part most likely to be new for a director moving from the website, because it belongs to filing through software. To use commercial software, you’ll need to set up an online filing account to get a presenter ID and presenter authentication code. You cannot use your Government Gateway account to send Companies House information online.

Companies House offers two kinds of account, and which one a company needs depends on what it files. You’ll need to apply for an account to file using software. The account you need will depend on whether you’re filing company accounts and documents that have a fee. If you only need to file company accounts, and documents that do not have a filing fee, you can use this service to apply for a presenter account.

Applying is short. GOV.UK says that you’ll need to:

• sign in or create an account
• give a name and correspondence address for the account
• give the name or company number of the business you work for

It takes around 5 minutes to apply. A filing that has a fee needs the other kind of account. You need a Companies House credit account to file documents that have a filing fee. For example, company incorporations and confirmation statements. Priya files her confirmation statement on the website, which stays open for it after 1 April 2028. Companies House web filing services will remain available and fully supported for non-accounts filings, including confirmation statements and updates to director details.

Account details get lost like any other login, and Companies House has a route for that too, under the heading “What to do if you’ve lost your presenter account details”. Use this service to submit an application. We’ll send you new account details.

One email a month lists the MTD software price changes we have checked and any changes to HMRC’s list of software. If that would be useful, you can sign up for the monthly price-changes email at the end of this page.

Looking back at what the company filed before

Before choosing software, it helps to know exactly which type of accounts the company has been filing. Companies House’s first step for directors who file their own accounts is to know what type of accounts you’re filing - you can ask a professional for advice. The company’s past filings are the easiest place to check. Our Find and update company information service makes all of the public data we hold on companies available free of charge. You do not need to register to view company information through this service. GOV.UK lists what the service shows, including the filing history of registered material and associated document images - images are free from 2003 onwards.

Some types of accounts have their own guide. The guide to dormant company accounts after April 2028 covers a dormant company. The guide to micro-entity and small company accounts after April 2028 covers a company that files micro-entity or abridged accounts.

Choosing software and making a first filing

With the code and the presenter account in place, the remaining steps are the ones Companies House sets out for directors who file their own accounts. You will need to:

• know what type of accounts you’re filing - you can ask a professional for advice
• find suitable software for the type of accounts you need to file
• contact your chosen software providers and consider changing to software filing as soon as possible
• make sure your chosen software is in place before 1 April 2028

Priya may already have some of what she needs. If you use software for another business process, such as payroll, you may be able to add an option to file your accounts with Companies House. Some commercial software will also allow you to file with HMRC at the same time. Check with your software provider for more information. Whatever she chooses, the software has to produce accounts in Inline eXtensible Business Reporting Language (iXBRL), the format Companies House will require. If you already use software to prepare or file accounts, check with your provider that it can support the new requirements. Not all software supports the iXBRL tagging you’ll need to file digital accounts. If you have any concerns about data protection when using commercial software, check your provider’s privacy policies and contact them directly for more information.

Our company filing hub links to GOV.UK’s two lists of software, and our monthly counts of the software used to file company accounts show which products companies file with today.

Filing early in the year gives room to deal with a rejection, and software tells the director quickly whether a filing went through. Some of the benefits of using software to file include:

• faster, more secure delivery with immediate acknowledgement of receipt
• automatic confirmation when your filing is accepted or rejected
• less chance of errors and rejected filings

Moving to software does not change when the accounts are due. The guide to company accounts and Company Tax Return deadlines sets out the deadlines and the penalties for filing late.

Keeping the code safe

Because the code works like a signature, anyone holding it can file for the company, so Companies House asks directors to guard it. You should treat your company authentication code with the same care as your bank card PIN. Anyone who knows your code is able to change your company’s details online. To look after your company authentication code:

• mix letters and numbers so your code is not easy to guess
• only share your code with someone you trust to file information for your company
• change your code if it’s known by someone you do not trust
• change your code if it’s known by someone who’s no longer authorised to file for your company (such as staff who’ve left your company, or your previous accountant)

Sign in to Companies House WebFiling to change or cancel your code. You can change your code to something more memorable, but do not make it easy to guess. We’ll never ask you what your company authentication code is over the phone. If you’re contacted by someone who asks for your code and claims to be from Companies House, you should report fraud to Companies House immediately.

If an accountant files for the company instead, the code is shared with them, and the guide for directors whose accountant files the accounts explains what stays with the director.

Questions about getting ready to file by software