What is a Cumulative Update?

A Cumulative Update is a summary of all your income and expenses so far in a given tax year — not just what’s changed since the last time you submitted. Instead of sending only the new information each time, you send the full picture from the start of the period up to now, including any changes or corrections you’ve made along the way.

This makes things a lot simpler. If you’ve had to tweak figures, add late invoices, or fix errors, those get picked up automatically in your next update. It keeps everything tidy and accurate without needing to send separate corrections — which is exactly what HMRC wants as part of Making Tax Digital.

When should I send a Cumulative Update to HMRC?

As a minimum you will need to send a Cumulative Update to HMRC once per quarter. The typical periods would be as follows for the 2026/27 Tax Year.

Quarter Start Date End Date Due Date
Q1 6th April 2026 5th July 2026 5th August 2026
Q2 6th April 2026 5th October 2026 5th November 2026
Q3 6th April 2026 5th January 2027 5th February 2027
Q4 6th April 2026 5th April 2027 5th May 2027

You can send as many Cumulative Updates as needed, offering flexibility to correct errors, add missing income or expenses, or simply generate a more up-to-date tax calculation.

Checking your Cumulative Update filing obligations

You can view your real-time cumulative update filing obligations from the Workflow page by selecting View Obligations from the Options menu. This page typically displays your four quarterly filing periods, along with their due dates and a status indicating whether each has been received by HMRC.

What information is included in a Cumulative Update?

You’ll need to file a separate Cumulative Update for each of your self-employment businesses, as well as an additional update if you have UK property income. Each update is based on accounting totals for a given period and typically includes your turnover, other income, and categorised expenses such as cost of goods sold, advertising, wages, and staff costs.

For self-employment, you’ll also need to include any disallowable expenses in your cumulative update.

You can find a more detailed breakdown of the cumulative update income and expense categories from the links below.

Separating your Property and Self-Employment Income

If you have a self-employment business and income from one or more UK properties, you’ll need to submit a separate cumulative update for each business, plus one update covering all your UK property income.

The nominal mapping feature lets you assign specific nominal codes to each income source, enabling you to manage both a self-employment and a property business within a single QuickFile account. However, if you operate multiple self-employment businesses, these must be managed across separate QuickFile accounts.

You can configure nominal mappings in the MTD Settings area by clicking the “Self-employment nominal account mappings” link.

Learn more about nominal mapping configuration →

What happens when all Cumulative Updates have been filed?

At the end of the tax year, once all cumulative updates have been submitted to HMRC, you’ll need to review your records to determine if any final adjustments are required or if additional income needs to be declared. The Self Assessment Workflow page helps you track your progress through this process.

If you need to make accounting adjustments or revise figures from previously submitted updates, you can do so directly from the workflow page.

Once all necessary adjustments and declarations are complete, you can proceed to your Final Declaration. This triggers a tax calculation for the year based on all data submitted to HMRC. You’ll be able to review the calculation, confirm the declaration, and submit it. At this point, your tax year is crystallised, and a payment schedule is generated for any tax due.

Consolidated Updates

If your annual income is expected to fall below the consolidated update threshold (£90,000 in 2025/26) you will be eligible to submit consolidated expense information to HMRC. This generally means that only a total of your expenses will be filed with HMRC, rather than a detailed breakdown.

QuickFile will determine if you income will exceed the threshold based on your pro-rata income for the period being filed. For example if your income is £25,000 for the period 6th April to 5th July, the expected annual income would be £100,000 for the year.

File your first Cumulative Update

When you are ready to file your first cumulative update you can review the following guide to help you get started.

Prepare and submit a cumulative update →

Apportioning an Update

In certain circumstances, your income and expenditure may need to be apportioned - for example, where amounts must be shared with a partner or spouse. In such cases, you can apply an apportionment percentage to a cumulative update before it is submitted to HMRC. QuickFile will then report only the adjusted totals.

Find out how to apportion a cumulative update

Any remaining percentage should be reported on the QuickFile account of your spouse or partner. You may share a cumulative update with any nominated QuickFile account as explained below.

Sharing Cumulative Updates (Split Reporting)

QuickFile allows you to share a cumulative update with a business partner or spouse for split reporting purposes.

When an update is shared, the report totals are visible to the recipient, but the backing transaction data remains accessible only on the originating (parent) account.

Prerequisites Before sharing an update, ensure the following conditions are met:

  • The recipient is listed as a Linked Account in the MTD settings area.
  • The recipient has approved the link request on their own QuickFile account.
  • The cumulative update on the parent account has a percentage apportionment set.
  • The cumulative update has been submitted to HMRC. The sharing option will not appear until the submission is complete.

1. Adding a Linked Account

To link a QuickFile account:

  1. Navigate to the MTD Settings area.
  2. Select the Linked Accounts tab.
  3. Enter the email address of the administrative user for the account you wish to link.
  4. An email will be sent to that user requesting approval.

2. Sharing a Cumulative Update

Once you have a linked account and have submitted your own apportioned return to HMRC, you can share the update.

  1. Open the specific report detail screen for the submitted return.
  2. Click the Options menu and select Share preferences.
  3. Select the linked account you wish to share the update with.

Once selected, the recipient will be able to import the update with the balancing apportionment, ready for filing to HMRC.

3. Importing a Shared Update (Recipient View)

On the recipient’s account, shared updates will appear in the main cumulative update list. The recipient can choose to Import or Discard the return.

If importing:

  1. The recipient must confirm the apportionment percentage. By default, this is set to the remaining balance not reported on the parent account.
  2. Once confirmed, the cumulative update is imported and set to DRAFT status.

Important Notes for Recipients:

  • Data Visibility: Only category totals, disallowables, and adjustments are imported. Detailed transactional data remains on the parent account.
  • Adjustments: Any adjustments made on the parent account are automatically apportioned. However, the recipient can edit or remove these adjustments within their own draft as needed.