Companies House has confirmed that major accounts filing reforms will come into force from 1 April 2028, giving small companies, micro-entities, accountants, directors, and software providers 21 months to prepare for one of the most substantial changes to UK corporate reporting in years.
Under the Economic Crime and Corporate Transparency Act 2023, all accounts filed on or after that date will need to be submitted through commercial software in inline extensible Business Reporting Language, or iXBRL, format. Companies House will close web and paper routes for accounts filings, although those channels will remain available for other statutory submissions.
The requirement applies to companies filing their own accounts and to those using accountants or third-party agents. Companies House said the move would create a “single, cost-effective, sustainable and traceable way to file”, while supporting wider efforts to improve the quality and reliability of data on the register.
Small companies and micro-entities will also have to file a profit and loss account as part of their annual accounts. They will be able to opt out of having that profit and loss account published on the public register, although further detail on the opt-out process is expected to follow.
Micro-entities will need to file a balance sheet and profit and loss account. Small companies will need to file a balance sheet, directors’ report, auditor’s report unless exempt, and profit and loss account. Small companies will no longer be able to prepare and file abridged accounts.
The reforms arrive as accountants and company finance teams are already adjusting to a heavier digital compliance environment. Making Tax Digital has turned quarterly submissions, client approvals, software readiness, and deadline management into live workflow questions for practices, with accountants facing practical gaps ahead of the MTD deadline.
Companies House reform will add another layer to that workload. Practices serving large numbers of micro-entities and owner-managed companies will need to decide how early to move clients onto compatible systems, how to price additional compliance work, and how to manage directors’ concerns over financial visibility.
Although the publication opt-out may reduce concerns over commercially sensitive information, it does not remove the obligation to prepare and submit more detailed data. Companies House, HMRC, and law enforcement bodies will have access to more financial information, strengthening the government’s corporate transparency and economic crime agenda.
Software-only filing is also likely to accelerate the shift away from manual processes in small-company finance. Businesses still relying on spreadsheets, paper records, or minimal year-end support will need a compliant product or an adviser with the right systems in place. Software providers now have a clear window to capture companies that have not yet digitised statutory reporting.
Directors will face tighter governance requirements alongside the accounting changes. Those claiming audit exemptions will need to provide an enhanced statement on the balance sheet, specifying which exemption is being claimed and confirming that the company qualifies. Companies shortening their accounting reference period more than once within five years will also need to provide a business reason.
The reforms move Companies House further away from a passive filing model and closer to an active data gatekeeping role. Better-structured accounts data should make the register more searchable, improve cross-government use of information, and reduce the scope for incomplete or low-quality filings.
Preparation will now depend on detailed guidance, software readiness, adviser capacity, and the final mechanics of the publication opt-out. Many small companies will be able to comply with support, but the shift changes the cost, visibility, and rhythm of routine financial reporting well before the April 2028 deadline arrives.
