SME Accounting News & Deep Dives: First MTD Filings Land, Tax Adviser Registration Opens & Budget 2026 Date Set

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Author: Sam Published: 19 August 2026

This week’s SME accounting news brings several important developments for limited companies and growing businesses.

HMRC has published the first results from Making Tax Digital for Income Tax. The second phase of mandatory tax adviser registration is now open. Companies House has delayed presenter identity verification requirements, while the date for Budget 2026 has been confirmed.

There is also a major planned reform to the way company tax computations are prepared and tagged for CT600 filings.

Here is what these changes mean for your business.

1. First MTD quarterly updates filed by more than 436,000 taxpayers

HMRC has confirmed that more than 436,000 sole traders and landlords filed their first quarterly update by the 7 August 2026 deadline. More than 570,000 taxpayers have signed up to Making Tax Digital for Income Tax so far.

Although this first stage applies mainly to unincorporated businesses, it is still relevant to limited company owners. Many directors and shareholders have personal property income, freelance income or another source of taxable income alongside their company activities.

MTD for Income Tax is separate from corporation tax and does not replace the annual company tax return. A limited company still needs to prepare its accounts and file its CT600 in the normal way.

The key points are:

• Quarterly MTD updates cover business and property income and expenses.

• The updates are in addition to, not instead of, the annual Self Assessment return.

• There are no penalties for late quarterly updates during the 2026–27 tax year.

• Penalties for late Self Assessment returns and late tax payments still apply.

• The points-based penalty system starts from 6 April 2027.

• The qualifying income threshold falls to over £30,000 from April 2027.

• The threshold falls again to £20,000 from April 2028.

The first quarterly deadline has now passed, but businesses should not treat the soft-landing period as a reason to delay. The next quarterly deadlines will arrive quickly, and digital record-keeping takes time to establish properly.

You can check the original HMRC deadline reference for the first MTD quarterly update.

What should limited company directors do?

If you operate only through a limited company, MTD for Income Tax is not a new company filing requirement. However, review whether you or another director has:

• Rental income

• A sole trader activity

• Partnership income

• Freelance or consultancy income

• Other taxable income that may bring you into MTD

A growing business should also keep personal and company records clearly separated. This makes it easier to assess whether a director has a personal filing obligation without confusing it with the company’s accounts.

2. Tax adviser registration phase two is now open

HMRC’s second registration window under the Modernising and Mandating Tax Adviser Registration programme opened on 18 August 2026.

This phase applies to advisers who:

• Have a Self Assessment or Corporation Tax agent account

• Do not hold an Agent Services Account

• Act for clients in relation to their tax affairs

Advisers in this group must register by 18 November 2026.

The first registration window attracted more than 4,000 applications, with over 2,000 Agent Services Accounts created. The figures show that HMRC’s new adviser framework is already creating a significant administrative task for accounting and tax practices.

There are later deadlines for some organisations. Payroll-only advisers and financial services organisations are not included in this phase and have separate registration windows.

Why this matters to SMEs

The legal duty to register falls on advisers rather than their clients. However, businesses may still feel the practical effects.

If an adviser is not properly registered, their ability to deal with HMRC could be restricted. This could create delays with:

• Corporation tax returns

• Self Assessment returns

• Tax repayment claims

• HMRC correspondence

• Client authorisations

• Tax enquiries

Growing companies should check that their accountant is prepared for the new registration requirements. When comparing corporation tax accountants, ask whether the firm can support your company’s tax filings, payroll and wider compliance needs under the new rules.

3. Companies House presenter verification pushed back

Companies House has moved back the expected deadline for presenter identity verification and mandatory Authorised Corporate Service Provider registration.

The requirements are now expected to begin no earlier than November 2027, rather than November 2026. Companies House has also confirmed that it will give presenters and third-party agents at least six months’ notice before the rules take effect.

This delay gives accounting practices and company formation agents more time to prepare their systems and processes.

It does not remove the wider direction of travel. Companies House is continuing to strengthen identity checks and improve the reliability of information filed about UK companies.

What should growing companies do now?

There is no need to make urgent changes solely because of the delayed presenter deadline. However, sensible preparation includes:

• Keeping director and shareholder information accurate

• Making sure company records are up to date

• Reviewing who is authorised to file documents

• Asking your accountant how future identity checks may affect your filings

• Avoiding last-minute confirmation statement and accounts work

The delay may be helpful, but it should not encourage businesses to leave company administration until the filing deadline.

4. Budget 2026 is set for 28 October

Budget 2026 will take place on Wednesday 28 October 2026.

No detailed SME tax measures have been confirmed yet, but the date is important for corporate tax planning. The Budget could affect decisions about investment, remuneration and the timing of transactions.

Limited companies should review three areas before the Chancellor’s statement.

Capital allowances

If your company is planning to buy equipment, vehicles or other qualifying assets, review the timing of that expenditure.

Capital allowance rules can influence the amount of taxable profit reported in the year. A corporation tax accountant can model whether bringing forward, delaying or staging investment is appropriate for your company’s cash flow and tax position.

Dividends

Dividend planning should be based on available distributable profits, cash flow and the shareholder’s personal tax position.

Avoid declaring dividends simply because the company has cash in its bank account. Your accountant should check the accounts, board documentation and available reserves before recommending a dividend.

Director remuneration

Salary, bonuses, dividends and pension contributions can have different tax and National Insurance consequences.

Before the Budget, growing SMEs should update their forecasts and review whether the current remuneration structure still fits the company’s expected profits and the director’s personal circumstances.

The safest approach is to plan using current rules, but keep enough flexibility to respond once the Budget measures are published.

5. Deep dive: the planned standardised CT600 computation reform

The most significant long-term development for limited companies is HMRC’s planned reform of company tax computations.

The CT600 will remain the company tax return, but HMRC is working towards a more standardised format for the computation submitted alongside it. The new format is expected to use consistent XBRL tagging, allowing tax information to be processed more reliably by software and HMRC systems.

The current timetable is:

• By September 2026: HMRC expects to publish the final specification.

• October 2026 to September 2027: Software providers will build and test their systems.

• October 2027 to September 2028: A live pilot is expected to take place.

• After the pilot: Wider implementation and mandation are expected to follow.

ICAEW has called for a longer pilot period, reflecting concerns that accountants, software providers and businesses need enough time to test the process properly.

What will change for SMEs?

For most small companies, the change will not be visible immediately. Your accountant or software provider will manage much of the technical work.

However, you may notice:

• New accounting and tax software updates

• Changes to the way tax computations are prepared

• More detailed data requirements

• Greater consistency between different companies’ filings

• Additional checks before a CT600 can be submitted

The aim is to make corporation tax filings more consistent and easier for HMRC to process. The transition may nevertheless create extra administration, particularly for businesses with unusual transactions, capital allowances, group structures or R&D claims.

How can your company prepare?

Growing SMEs should not wait until the live pilot begins to improve their records.

Start by making sure:

1. Bookkeeping is kept up to date throughout the year.

2. Capital purchases are recorded with dates, descriptions and supporting invoices.

3. Director transactions are clearly identified.

4. Loans, dividends and related-party transactions are documented.

5. R&D expenditure is supported by a clear evidence trail.

6. Your accounting software can produce compliant accounts and tax computations.

7. Your accountant is monitoring changes to CT600 and XBRL requirements.

A good limited company accountant should explain what software changes are likely to affect your business and whether any new information will be needed during the year.

Your SME action list for this week

For limited company directors and growing SME owners, the practical priorities are:

• Check whether you or another director may be affected by personal MTD for Income Tax.

• Confirm that your accountant is ready for HMRC’s adviser registration requirements.

• Keep company records accurate ahead of future Companies House identity checks.

• Review planned capital expenditure before Budget 2026.

• Revisit dividend and director remuneration plans.

• Ask whether your accounting software is ready for future CT600 computation reforms.

• Maintain clear digital records rather than relying on a year-end catch-up.

Self-Assessment tick-box: [ ] Check whether you, your fellow directors or shareholders have personal income that creates a Self Assessment or future MTD obligation.

If you need help with a personal tax return, complete our SA registration form through our Self Assessment accountant service. For company accounts, tax returns or ongoing support, you can also find an accountant matched to your business needs.

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