Making Tax Digital for Income Tax Self Assessment (MTD ITSA) replaces the annual tax return with quarterly cumulative updates and a final declaration. This guide takes sole traders and landlords through all 18 steps in QuickFile, from checking that MTD applies to you to submitting your final declaration.

It has four parts: Before you start (steps 1 to 4), Connect QuickFile to HMRC (steps 5 to 7), Quarterly cumulative updates (steps 8 to 13) and End of the tax year (steps 14 to 18). Each step links to the full support articles.

The screenshots use a test account connected to an HMRC sandbox, so the names and figures are fictional. Common questions, the full video library, the HMRC reporting categories and notes for accountants are in the online guide.

Prefer to watch?

Prefer a video walkthrough? Watch our MTD for Income Tax in QuickFile: The Complete Step-by-Step Guide tutorial on the QuickFile Help Guides YouTube channel.

Before you start

• A sole trader or landlord QuickFile account (MTD for Income Tax isn’t available in limited company accounts).
• A Power User subscription, or the Affinity MTD Self Assessment add-on (step 4).
• A sign-up for MTD for Income Tax with HMRC and your Government Gateway user ID (step 3).

Key dates for 2026/27

Each update covers everything from the start of the tax year to the end of the quarter. You can send updates as often as you like, but you must send at least one for each quarter.

Deadlines are from GOV.UK. QuickFile’s View obligations screen shows the same due dates (step 7). *In 2026/27 only, 1 to 5 April is reported through a BSAS adjustment if you use calendar quarters (step 14).

Step 1: Check if MTD for Income Tax applies to you

MTD for Income Tax replaces the single annual tax return with quarterly updates and a final declaration. It applies to sole traders and landlords registered for Self Assessment whose qualifying income is over HMRC’s threshold.

What counts as qualifying income

• Your self-employment turnover plus your property income, added together, before expenses are taken off.
• It does not include PAYE wages, partnership profit shares, dividends or pensions.
• If you own a property jointly, only your share of the rent counts.

• GOV.UK: Check if you’re eligible
• GOV.UK: Work out your qualifying income
• GOV.UK: Exemptions from MTD for Income Tax

Step 2: Decide how many QuickFile accounts you need

Work this out before you set anything else up. One QuickFile account can hold one self-employment business, any number of UK properties and one foreign property, and send a separate update to HMRC for each. If you have two sole-trade businesses registered with HMRC, you need two QuickFile accounts and submit each business from its own account.

Enter your businesses and properties in the MTD account configurator. It tells you how many accounts you need and how many updates you’ll send each year. This matters because each cumulative update is built from one account’s chart of accounts: if two businesses share an account, their figures get mixed together.

What the configurator recommends

Everyone also sends one final declaration a year, however many accounts they have.

Setting up more than one account

• Business and rent in one account? Use separate nominal codes for the rent (for example 4904 Rent Income, QuickFile’s default rent income code, rather than 4000 Sales), so each code can be mapped to the right income source in step 8. One nominal code can’t be mapped to both UK and foreign property.
• Joint property? Keep the bookkeeping in one account. Each owner who files needs their own QuickFile account. Step 11 shows how to split the figures.
• Several accounts? Affinity lets you manage them all under one login.
• Hide what you don’t report. HMRC lists all your businesses in every account you connect, so hide the ones each account doesn’t report (step 6).

• Video: Affinity Overview: Managing Multiple Accounts (2:24)
• Video: Sole Trader Bookkeeping Basics (5:24)
• Video: Landlord Bookkeeping Basics (5:02)
• Video: How to Add a New Nominal Account (2:08)
• Mapping rules

Step 3: Sign up for MTD with HMRC

QuickFile can only find your self-employment and property businesses once you are signed up to MTD for Income Tax with HMRC. Do this first.

1. Open HMRC’s sign-up page for Making Tax Digital for Income Tax.
2. Sign in with the Government Gateway user ID you use for Self Assessment. HMRC may ask you to confirm your identity.
3. Confirm your business details (name, address and trade) and finish the sign-up.

Step 4: Get the right QuickFile subscription

You need a Power User subscription to use the MTD Income Tax and Self Assessment module. You can’t submit MTD updates on the free plan. MTD for Income Tax is for individuals, so it works in sole trader and landlord accounts, not in a limited company account.

How to buy Power User

1. Click your company name in the top right corner and choose Services / Subscriptions.

   

2. Click Update or add a new subscription.

   

3. Tick Power User Subscription and complete the purchase. Automated Bank Feeds is a separate, optional service and isn’t needed for MTD.

   

4. Log out and back in if the new features don’t appear straight away.

• Power User Subscription
• Affinity MTD ITSA add-on

Step 5: Connect your HMRC tax account

1. From the top menu choose Reports > HMRC Connections. The screen that opens is called HMRC Tax Accounts.

   

2. Click Connect.

   

3. Give the account a name and choose Individual account. Individual is for Self Assessment; Organisation is only for VAT.

4. Click Continue. You are taken to HMRC to sign in.

5. Sign in with the Government Gateway ID for your Self Assessment and confirm that QuickFile can access your account.

6. You are sent back to HMRC Tax Accounts and the tax account appears under Direct Connections.

   

Check the connection is working

Look at the Status column: Good means QuickFile can read your HMRC data, and Failed means you need to reconnect. Click view to open the tax account and see your MTD businesses. The red X under Disconnect removes the connection.

• Video: Connecting Your HMRC account (Self Assessment) (2:18)
• HMRC Tax Accounts

Step 6: Check your business details and accounting method

1. On HMRC Tax Accounts, click view next to your tax account. Under MTD for Self Assessment Businesses you see every business HMRC has linked to you, with its type, an Options button and a Workflow link.

   

2. Click the business name to open its details.

3. Check what HMRC holds for that business: trading name, business type, trading type, address, accounting period, accounting type (cash or accrual, with an update link), commencement date, quarterly filing choice and periods of account.

   

4. Check each business in turn. If anything is wrong, update it with HMRC, because QuickFile shows HMRC’s records.

The same details are under View business details in the business’s Options menu, which also has View obligations, View cumulative updates, View / Amend Annual Summary, View Business Income Source Summary and Hide business.

Cash or accrual?

• Cash accounting: income and costs count when invoices and purchases are paid.
• Accrual (standard) accounting: they count when invoices and purchases are issued.

The method QuickFile uses for your updates is set in MTD Settings (step 8). It must match the one registered with HMRC.

Standard or calendar quarters

From 2026/27 you can choose calendar quarters (for example 1 April to 30 June) instead of the standard ones (6 April to 5 July). QuickFile only offers this if your accounting period runs from 1 April to 31 March. If you’re eligible, click (update) next to Quarterly filing choice on the Business Details screen. Until you choose, it shows Not Specified.

Hide businesses you don’t use in this account

If you split your businesses across several QuickFile accounts, hide the ones you don’t report: on the tax account page, click Options next to the business and choose Hide business. It no longer appears in the workflow, obligations or update menus.

• Video: Check Your Self-Assessment Business Details (2:31)
• Video: Using Calendar Quarters for MTD ITSA from 2026/27 (2:38)
• Check your business details
• Using calendar quarters
• Periods of Accounts

Step 7: Open the Self Assessment Workflow and check your obligations

The Self Assessment Workflow is where you manage the tax year: quarterly updates, adjustments, other income and the final declaration.

1. Go to Reports > Self Assessment. You can also click Workflow next to a business on the tax account page.

   

2. Choose the Tax Year and the Income Source (for example your self-employment or UK property business) at the top.

The workflow runs from top to bottom through the year:

• Cumulative Updates: Q1 to Q4, each marked Due or Not due. Click New Update, or Due next to a quarter, to prepare one.
• Business Source Adjustment Summary (BSAS): year-end adjustments once all four updates are in.
• Allowances and Adjustments: self-employment only, optional.
• Other Income Sources: optional, for income outside the business such as employment, dividends or savings.
• Final Declaration: the last step for the year.

Each stage shows INCOMPLETE until it is done. Click the arrow on the status to see what the stage is for.

1. To see every deadline, click Options > View obligations at the top right of the Workflow.

   

2. Filter by tax year or business. The Cumulative Updates tab lists each period with its due date and status, and the Final Declaration tab shows when that is due. Click Prepare to start a draft update for a period.

   

The Options menu also has Request a Tax Calculation, View cumulative updates, View / Amend Losses Brought Forward, View Business Income Source Summary, View Business Information, Show MTD Status and MTD Settings.

• Self-Assessment Workflow
• Checking your obligations

Step 8: Set up your nominal mappings

Mapping rules link each nominal code in your chart of accounts to an HMRC reporting category. You can keep separate sets of rules for self-employment, UK property and foreign property.

1. In the Workflow, click Options > MTD Settings.

   

2. On the General tab, check the HMRC Account, choose the Linked Business and check the Accounting Method and MTD Start Date. Click Save Settings if you change anything. Then click the mappings link under the business type, for example Self employed nominal account mappings.

   

3. Use the Business type drop-down at the top of the mapping screen to switch between self-employment, UK property and foreign property mappings.

   

4. Self-employment starts with a default set of rules (Template: Default). Expand a category to see its nominal codes. Click Add new mapping to add a code, or the x to remove one.

   

5. To report a self-employment expense as disallowable, tick Mark as disallowable when you add the nominal code.

6. At the bottom of each section, choose where any unmapped codes should go, for example Unmapped Income (4000-4999) - Post to.

Property mappings

UK property and foreign property start with no mappings, so you add your own. Give each property business its own nominal codes, for example 4904 Rent Income for rent and separate codes for repairs and letting agent fees.

1. Choose UK Property (or Foreign Property) in the Business type drop-down.

2. Expand a category, click Add new mapping, choose the Nominal account name and click Add nominal code.

   

3. Repeat for each code. Rental income goes under Total rental income from property.

   

You can also open the mappings from a draft update with Options > Configure Mappings.

Fixing mapping conflicts

A conflict means the same nominal code is mapped to more than one business, for example 7603 Professional Fees under both self-employment and UK property. The same amount would then be reported to HMRC twice. QuickFile warns you at the top of every mapping screen.

1. Click view in the warning. It lists each conflicting code and where it is found.

   

2. Decide which business each code belongs to. If both use it, create a separate nominal code for the second business (for example UK Property Letting Agent Fees) and post those transactions to it.

3. Use the Business type drop-down to open the other business, expand the category and click the x next to the code to remove it. Click OK to confirm.

4. Reload the mapping screen. When every conflict is fixed, the warning disappears.

• Video: Cumulative Update Mapping Rules Explained (3:22)
• Configuring nominal mappings
• Mapping rules

Step 9: Create a new cumulative update

A cumulative update is the total of your income and expenses from the start of the tax year up to the end of the period. It isn’t just the last three months. Each update replaces the one before, so any corrections are picked up automatically next time.

1. In the Self Assessment Workflow, click New Update. You can also click Due next to the quarter.

   

2. The New Cumulative Update box opens. It shows the Accounting Method from your MTD Settings. Choose the Business Entity, then the earliest open Update Period. Use Manual Entry if you need a custom date range, but it must match HMRC’s periods.

   

3. Click Create.

4. QuickFile explains which basis the report uses (for example cash-based, worked out from payment dates). Click Generate new report.

   

• Video: Completing your Cumulative Update (Self Employed) (3:10)
• Video: Submit a UK Property Cumulative Update (4:41)
• Prepare and submit a cumulative update
• Cumulative Updates explained

Step 10: Check your draft, add disallowables and adjustments

1. The new draft shows your totals grouped into HMRC categories, with the time it was generated. Click rebuild to refresh it after changing your bookkeeping.

   

2. Use the tabs to switch between Group by HMRC Categories and Group by Nominal Accounts. Click any total to see the invoices and payments behind it.

   

3. Check the figures against your Profit and Loss report for the same dates. Use the cash-based report if you use cash accounting.

4. Click Save as Draft at the bottom. Before saving, the Options menu only has Configure Mappings and Discard Draft.

   

5. Once saved, the status shows DRAFT and an Adjust column appears. Click the plus icon next to a category to declare disallowable expenses or make small adjustments.

   

6. In New Adjustment, check the category under Apply to, enter the Amount and any Notes, then click Create.

   

Your drafts are listed under Options > View cumulative updates in the Workflow, on the Draft tab. Click View to open one.

• Video: How to Generate a Cash Based Profit & Loss Report (3:37)
• Generate a cash based Profit and Loss report
• Self-employment categories
• UK property categories

Step 11: Split a jointly owned property (apportion and share)

If you share income and expenses with a spouse or business partner, you can report your percentage only. The other person reports the rest from their own QuickFile account.

Apportion your update

1. Save the update as a draft, then click Options > Apply apportionment.

   

2. Enter your Percentage Application (between 1 and 99) and click Save. Only the category totals sent to HMRC are adjusted; your bookkeeping doesn’t change. Leave it blank to remove the apportionment.

   

Share the rest with the other owner

1. In MTD Settings, open the Linked Accounts tab and click Link Account. Enter the email of the admin user on the other QuickFile account. They get an email to approve the link, and the account then shows as Active.

   

2. Submit your apportioned update to HMRC. The share option only appears after you’ve submitted.

3. Open the submitted update, click Options, then Share preferences, and pick the linked account.

   

4. The other owner sees the update in their list and clicks Import. The percentage defaults to the remaining share. It comes in as a draft, ready for them to check and submit.

• Video: Sharing & Apportioning a Cumulative Update (6:08)
• Sharing cumulative updates

Step 12: Submit to HMRC and view your tax calculation

1. Open your saved draft. Your NET Income is shown at the bottom. Click Submit Update.

   

2. A summary of your totals appears, and it tells you if you can use consolidated expenses.

3. Click Submit Cumulative Update to send it to HMRC.

4. HMRC works out a new tax calculation after each update. When the link appears, click it to view the report.

Request a tax calculation at any time

1. In the Workflow, click Options > Request a Tax Calculation.

   

2. Past calculations are listed under MTD Tax Calculations on the tax account page (Reports > HMRC Connections, then view).

• Video: How to Request a Tax Calculation (1:31)
• Request a tax calculation

Step 13: Send foreign property updates

1. Once your tax account is linked and you are signed up with HMRC, your foreign property business appears on the tax account page.

2. Before your first update, tell HMRC about the properties. Click the business name to open its details, then click View and update next to Foreign Properties.

   

3. Click Add Foreign Property and add a name and country for each property or group of properties. The list shows everything registered with HMRC for the selected tax year.

   

4. In the Workflow, choose the foreign property business as the Income Source, then click New Update (or Due) and pick the period.

5. If you haven’t registered a property yet, QuickFile offers to do it now. Click OK to register it, or Cancel to carry on.

   

6. In the draft, choose the property from the Foreign Property drop-down and say whether you are claiming Foreign Tax Credit Relief. Check the figures, save the draft, then submit.

   

• Video: QuickFile Foreign Property Updates (2:04)
• Foreign Property Updates

Step 14: Make year-end business adjustments (BSAS)

A Business Source Adjustable Summary (BSAS) lets you adjust the figures from your quarterly updates for one business once all of them are submitted, for example for capital allowances, disallowable expenses and use of home as an office. You must submit one to confirm your totals, even if you make no changes.

1. In the Workflow, find the Business Source Adjustment Summary (BSAS) stage under your quarterly updates. It shows INCOMPLETE until it is done, and it opens once all four updates are in.

   

2. Open the stage, click New Adjustments and choose the business and the period.

3. Enter your adjustments against the right HMRC categories. Enter only the change to each figure, not the new total.

4. Submit the adjustments to HMRC, then request a new tax calculation so your tax position is up to date.

• Business Source Summary Adjustments (BSAS)

Step 15: Record trading losses

If your allowable expenses were more than your income, you may be able to use the loss against other income, carry it back a year or carry it forward to future profits from the same trade.

1. In the Workflow, click Options > View / Amend Losses Brought Forward.

   

2. Choose the tax year the loss is brought forward from and the Business. Losses already recorded are on the Losses Brought Forward tab, and claims on the Loss Claims tab.

   

3. Click Record Loss Brought Forward, check the business and From Tax Year, and enter the Loss Amount.

   

4. Click Save. The details go to HMRC straight away. You can change or delete them until your final declaration is filed.

• Trading Losses and Loss Claims

Step 16: Check your Business Income Source Summary (BISS)

The BISS shows HMRC’s figures for one business for the tax year: income, expenses, additions (amounts added back, such as disallowable costs) and deductions. The totals at the bottom show the net figure and the profit.

1. In the Workflow, click Options > View Business Income Source Summary. It is also in the business’s Options menu on the tax account page.

   

2. Choose the Tax Year and Business to see that business’s summary.

   

• Business Income Source Summary

Step 17: Add your other income

Your final declaration covers all your income, not only your business. Before you submit it, add any other income from the Other Income Sources stage of the Workflow (it is marked OPTIONAL), for example:

• PAYE employment income
• Dividends
• Savings and pension income
• Capital gains and residential property disposals
• Foreign income
• Income from insurance policies
• Other non-PAYE employment income
• Charges such as the High Income Child Benefit Charge

QuickFile’s guidance explains each field: Employments, Dividends, Disclosures and Charges.

Step 18: Submit your final declaration

The final declaration replaces the old tax return. It confirms your total income, reliefs and allowances for the year and triggers HMRC’s final tax calculation. For 2026/27 it is due by 31 January 2028.

1. Make sure all four quarterly updates are submitted, and add any adjustments and other income.

2. Open the Final Declaration stage at the bottom of the Workflow.

   

3. If the tax year hasn’t ended yet, QuickFile tells you so and offers a link to file the previous year instead.

   

4. Click Generate a Final Tax Calculation. HMRC shows your total income and your Income Tax and National Insurance.

   

5. If everything is correct, read and accept the declaration, then submit it to HMRC. The accounting period for that year is then locked.

HMRC then finalises (crystallises) the tax year and sets up a payment schedule for any tax you owe. MTD doesn’t change how or when you pay.

See what you owe and what you’ve paid

1. On your tax account page, click Options > View HMRC financial statement at the top right. You see your liabilities (overdue, due now and not yet due) and your payments to HMRC.

   

Years before you joined MTD are still in your HMRC personal tax account.

• Video: How to Submit Your Final Declaration (2:07)
• Final Declaration
• Payments and Liabilities

Related topics

New to MTD for Income Tax? Start with Making Tax Digital (MTD) for Income Tax: A Guide for Existing Users for a short overview, then use the articles below for the detail behind each step.

• Making Tax Digital (MTD) for Income Tax: A Guide for Existing Users: A short overview of what changes, the key dates and how to prepare.
• Self-Assessment Workflow: How the workflow stages fit together through the tax year.
• Cumulative Updates: What a cumulative update is and how each period works.
• Prepare and Submit a Cumulative Update: Create, check, save and submit a draft update in detail.
• Cumulative Update Mapping Rules: How nominal codes are matched to HMRC categories.
• Foreign Property Updates: Register foreign properties and send their updates.
• Final Declaration: The year-end declaration screen by screen.
• About the MTD Other Income Guidance category: Where to find the guidance for each other income form.
• Understanding The MTD For ITSA Cumulative Updates (blog): A plain-English explanation of how cumulative updates work.