When are the Annual Accounts Filing Deadline for UK Property Companies

If you have just tried to log into the HMRC and Companies House joint filing portal to file your property company's accounts and found it no longer exists, you are not alone. The free service that thousands of landlords relied on closed permanently on 31 March 2026, and the change has caught many SPV directors off guard.

This article sets out the filing deadlines that apply to your property company, explains the penalty regime if you miss them, and covers what you now need to do differently following the closure of the joint filing service.

Company Accounts Filing Deadlines for Companies House & HMRC

One of the most common mistakes property company directors make is treating their statutary filing obligations as a single event. There are three separate deadlines, each with its own recipient, its own penalty regime and its own consequences for getting it wrong.

These are three entirely separate obligations. Filing your accounts with Companies House does not satisfy your duty to HMRC. Submitting your CT600 does not mean you have filed with Companies House. And filing the return does not mean you have paid the tax. Each one must be dealt with individually and on time.

How Does the Accounting Reference Date Work

Every deadline flows from one date: your company's accounting reference date (ARD). This is the last day of your company's financial year, and it is set automatically by Companies House when the company is incorporated. By default, it falls on the last day of the month in which the anniversary of incorporation occurs.

For example, if your BTL SPV was incorporated on 15 July 2023, the ARD would be set as 31 July each year. All three deadlines above are then calculated from that date.

For the first set of accounts, the rules are more generous. A newly incorporated company has 21 months from the date of incorporation to file its first accounts with Companies House. The first accounting period can cover a maximum of 18 months. From the second year onwards, the standard nine-month deadline applies.

It is important not to confuse the Companies House accounts deadline with the Corporation Tax filing deadline. The first CT600 Company Tax Return is due to HMRC 12 months after the end of the Corporation Tax accounting period. A Corporation Tax accounting period cannot exceed 12 months, so if the first set of accounts covers more than 12 months, HMRC will usually require two CT600 returns: one for the first 12 months and one for the remainder. Each Corporation Tax period may also have its own payment deadline.

What Changed on 1 April 2026

For years, the joint HMRC and Companies House online filing service allowed company directors to prepare and submit their annual accounts and CT600 in a single process, free of charge. Many landlords who set up BTL SPVs used this portal to self-file without needing an accountant or paid software. It was straightforward and it cost nothing.

That service closed permanently on 31 March 2026. From 1 April 2026, the two filing obligations must be dealt with separately, and the CT600 can only be filed using HMRC-recognised commercial software that produces the return in iXBRL format. There is no longer a free web form for Corporation Tax filing, except in very limited circumstances involving paper returns where HMRC accepts a reasonable excuse.

For Companies House, accounts can still be submitted through the Companies House Web Filing service, through commercial software, or on paper.

There are two further points that many directors have overlooked. First, previously filed returns are no longer accessible through the old portal. If you need to refer to earlier submissions, whether for your own records, a compliance check by HMRC, or when instructing a new accountant, those records are gone unless you downloaded them before the service closed. Second, if you need to amend a previously submitted CT600 or refile a rejected return, you must now do so through commercial software or by posting a paper return to HMRC's Corporation Tax Services office.

The practical effect for a BTL SPV director filing for the first time since the change is this: you need to either purchase commercial filing software or instruct an accountant. Self-filing for free is no longer an option for the Corporation Tax Return.

Worked Example: A Typical BTL SPV

Sam incorporates a company on 10 September 2023 to buy a rental property. The company is a special purpose vehicle, or SPV, meaning it has been set up for a specific purpose: holding the buy-to-let property.

Companies House automatically gives the company an accounting reference date of 30 September each year. This means the first accounts will run from 10 September 2023 to 30 September 2024.

First year (extended period)

Sam's first accounting period runs from 10 September 2023 to 30 September 2024.

As this is her first set of accounts, she has 21 months from incorporation to file with Companies House. That gives her until 10 June 2025.

Her first CT600 is due 12 months after the accounting period end, so by 30 September 2025. Her first Corporation Tax payment was due by 1 July 2025 (nine months and one day after 30 September 2024).

Second year onwards

Sam’s second accounting period runs from 1 October 2024 to 30 September 2025.

 Her Companies House filing deadline is nine months later: 30 June 2026. Her CT600 is due by 30 September 2026. Her Corporation Tax payment is due by 1 July 2026.

What Are the Penalty Regime for Late Filing of Company Accounts

Companies House imposes automatic penalties for late filing of accounts. There is no discretion, no reminder period and no appeal on the basis of a reasonable excuse. The penalties for private companies are:

If accounts are filed late in two consecutive financial years, the penalty for the second year is automatically doubled. A company that files two months late for two years running would face £375 for the first year and £750 for the second.

Example: doubled penalty for repeated late filing

A company’s accounts are due at Companies House by 30 June 2026.

The company files the accounts two months late, on 31 August 2026. Because the accounts are more than one month late but not more than three months late, the penalty is:

The following year, the company again files its accounts two months late. Because this is the second consecutive financial year in which the accounts have been filed late, the penalty is automatically doubled:

HMRC has its own separate penalty regime for late CT600 returns. For Company Tax Returns with a filing deadline on or after 1 April 2026, the fixed penalty starts at £200 and further penalties can apply if the return is more than three, six or twelve months late. Interest also runs on unpaid Corporation Tax from the day after the payment deadline.

Interest also runs on any unpaid Corporation Tax from the day after the payment deadline.

These penalties are cumulative. A property company that misses both the Companies House and the HMRC deadlines will face penalties from both bodies, and neither will accept the other's filing as a substitute.

Statutary Filing Starts When the Company Exists, Not When the Project Completes

This is a point that catches out more directors than it should. If you have incorporated a company to carry out a property development, your filing obligations begin from the date of incorporation, not from the date the project completes or the date you first make a profit.

A company that was incorporated 18 months ago to develop a site but is still mid-build, with no rental income and no sales proceeds, must still file accounts with Companies House by the normal deadline. The accounts may show little more than setup costs and a development work-in-progress balance, but they must still be prepared and filed. For Corporation Tax, the company may also need to file a CT600 if HMRC has issued a notice to deliver a Company Tax Return, even if there is no Corporation Tax to pay. Directors of development companies should not assume that filing can wait until completion. Late filing penalties can still apply.

How Do You Change Your Accounting Reference Date?

Property company directors sometimes want to change their company's year-end to align with a refinance completion, a calendar year, or the tax year. This is done by filing form AA01 with Companies House, and the rules are as follows.

A company can shorten its accounting period as often as it wishes, and by as many months as it likes. There is no restriction on shortening.

Extending the accounting period is more restricted. A company can usually lengthen its financial year only once every five years, and the extended period must not exceed 18 months from the start of the accounting period. Exceptions apply where the company is in administration, where the change aligns the year end with that of a UK parent or subsidiary undertaking, or where Companies House gives special approval.

Any change must be filed before the accounts filing deadline for the period being changed. If accounts are already overdue, it is too late to change the ARD.

Annual Accounts Deadlines for Non-Resident Directors and Overseas Entities

The annual filing deadlines apply equally to companies with non-resident directors. If you are based outside the UK but direct a UK-registered property company, the obligations are the same: nine months for Companies House accounts, twelve months for the CT600, and nine months and one day for the tax payment.

What has changed is the compliance environment around those obligations. Since 18 November 2025, company directors and persons with significant control must verify their identity with Companies House under the reforms introduced by the Economic Crime and Corporate Transparency Act 2023.

This applies regardless of where the director is based. Existing directors are being brought into the regime through a 12-month transition period, but this does not mean every director has until November 2026.

In practice, an existing director will usually need to verify and provide their Companies House personal code when the company files its next confirmation statement, so the actual deadline depends on that company’s confirmation statement date. For some companies, that could fall very soon after 18 November 2025. New directors must verify before incorporation or appointment.

For overseas directors, the verification process can involve additional steps. Those without a biometric UK passport or driving licence may need to verify through an Authorised Corporate Service Provider or attend a Post Office branch in person. Without a verified identity and the resulting Companies House personal code, a company cannot file its confirmation statement, and a blocked confirmation statement can disrupt the wider compliance timetable including accounts filing.

Separately, overseas legal entities that own, or wish to buy, sell or transfer, UK land or property may need to register with Companies House on the Register of Overseas Entities and provide details of their registrable beneficial owners or managing officers. They must also file an annual update statement, even where nothing has changed. This is a separate compliance obligation and does not replace any UK tax filing or accounts filing requirements that may also apply.

Conclusion: Don't Wait Until It's Too Late

If your property company's next company accounts filing deadline falls after 1 April 2026, the old joint filing route is no longer available to you. The steps to take are straightforward:

Confirm your accounting reference date and calculate your three deadlines: Companies House accounts, CT600, and Corporation Tax payment.

If you previously used the free joint filing portal, check whether you downloaded your earlier returns before the service closed. If not, those records are no longer accessible online, and you may need to request copies from HMRC directly.

Decide how you will file going forward. The old joint filing service closed on 31 March 2026, so CT600 returns now usually need to be filed using commercial software or through an accountant. Companies House filing options depend on the type of accounts. Software-only filing is still expected in future, but the April 2027 date is no longer current, so companies should check the latest Companies House position before buying software.

If your company has not yet filed its first accounts, remember that the 21-month deadline from incorporation is not as generous as it sounds. Property companies often have more complex accounts than a straightforward trading company and leaving everything to the final weeks is a reliable way to trigger an avoidable penalty.

Filing company accounts and tax returns on time is not optional, and the consequences of getting it wrong are immediate and automatic. The closure of the free joint filing portal in April 2026 has added a practical hurdle for many property company directors who previously managed their compliance without professional support.

With the CT600 now requiring commercial software and Companies House moving towards software-only filing in the near future, staying on top of your obligations requires more planning than it once did.

How UKPA Can Help

At UKPA, we work with property company directors and landlords across the UK to ensure their compliance obligations are met accurately and on time. Our team understands the specific requirements of property companies, from rental income schedules and mortgage interest calculations to capital allowance claims and the correct treatment of investment property

Whether you run a single property SPV, a growing portfolio company or a development vehicle that has not yet completed its first project, the deadlines apply from the moment the company exists. Understanding your accounting reference date, knowing your three filing dates and acting well before the deadline is the most reliable way to avoid penalties and keep your company in good standing, which you can trust on UKPA.