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MTD for Income Tax: What UK Accounting Firms Need to Know

Making Tax Digital for Income Tax is coming in April 2026. Here is everything your firm needs to understand, prepare for, and communicate to clients.

What Is MTD for Income Tax?

Making Tax Digital for Income Tax Self Assessment (MTD for ITSA) is the next phase of HMRC's Making Tax Digital programme. It requires self-employed individuals and landlords to keep digital records and submit quarterly summary updates to HMRC using MTD-compatible software.

This replaces the traditional annual self-assessment tax return with a more frequent reporting cycle: four quarterly updates, an end-of-period statement, and a final declaration.

For accounting firms, this means a fundamental shift in how you manage self-assessment clients. Instead of one annual touchpoint, you will have at least five interactions per client per year, with digital record-keeping requirements throughout.

Key Dates and Deadlines

April 2026

MTD for Income Tax becomes mandatory for self-employed individuals and landlords with income over £50,000.

April 2027

Extended to those with income over £30,000.

TBC

Further rollout to partnerships and lower income thresholds expected in subsequent years.

What Changes for Accounting Firms?

MTD for ITSA is not just a software change. It fundamentally shifts the relationship between your firm and your self-assessment clients:

Quarterly touchpoints

Instead of gathering everything at year-end, you will need processes for collecting and reviewing data quarterly. This requires new workflows and capacity planning.

Digital record-keeping

Clients must keep digital records. Those still using spreadsheets or paper will need to move to MTD-compatible software before the mandate takes effect.

Compatible software

Your firm needs software that can submit quarterly updates to HMRC. Check that your current tools support MTD for ITSA, not just MTD for VAT.

Fee restructuring

More frequent touchpoints mean more work. Many firms are reviewing their fee structures now to reflect the increased service level required under MTD.

Which Software Is MTD-Compatible?

The main cloud accounting platforms used by UK firms are all working on MTD for ITSA support. Here are the tools we recommend reviewing:

Dedicated tax compliance software like TaxCalc and TaxFiler also support MTD filing. See our tech stack guide for a full overview.

How to Prepare Your Firm

1

Audit your client base

Identify which of your self-assessment clients fall above the £50,000 threshold and will be affected from April 2026.

2

Check software compatibility

Confirm your accounting software supports quarterly updates and HMRC MTD for ITSA submissions. Xero, QuickBooks Online, Sage, and FreeAgent all have MTD roadmaps.

3

Migrate clients to cloud bookkeeping

Clients still using spreadsheets or manual records will need digital record-keeping. Start migrating them to a compatible platform now.

4

Set up quarterly workflows

MTD requires quarterly summary updates to HMRC. Build recurring workflows in your practice management tool (Karbon or Senta) to handle the increased touchpoints.

5

Train your team

Ensure staff understand the quarterly submission process, how to use MTD-compatible software for ITSA, and how to communicate changes to clients.

6

Communicate with clients early

Do not wait until 2026. Send clear, jargon-free communications explaining what is changing, what clients need to do, and how your firm will support them.

Not sure where you stand?

Take our free MTD Readiness Checker to get a personalised score and action plan.

Take the MTD Readiness Assessment

How to Prepare Your Clients

Client communication is critical. The firms that start early will have smoother transitions and happier clients. Here is what we recommend:

Send a plain-English letter or email explaining what MTD for Income Tax means for them specifically.

Offer a short meeting or call to walk through the changes and answer questions.

Recommend a cloud bookkeeping tool if they are not already using one (Xero or FreeAgent for smaller clients).

Set expectations around quarterly touchpoints and any changes to fees.

Provide a simple checklist of what they need to have ready before April 2026.

Frequently Asked Questions

What is MTD for Income Tax?

Making Tax Digital for Income Tax Self Assessment (MTD for ITSA) requires self-employed individuals and landlords to keep digital records and submit quarterly summary updates to HMRC using compatible software, rather than filing a single annual self-assessment return.

Who is affected by MTD for Income Tax?

Initially, self-employed individuals and landlords with annual gross income over £50,000 from April 2026. Those with income over £30,000 will be included from April 2027. Partnerships and lower thresholds are expected to follow.

What software is MTD-compatible for Income Tax?

HMRC maintains a list of compatible software. The main platforms used by UK accounting firms (Xero, QuickBooks Online, Sage Accounting, and FreeAgent) all have MTD for ITSA support on their roadmaps. Dedicated tax software like TaxCalc and TaxFiler also support MTD filing.

What are quarterly updates?

Under MTD for ITSA, taxpayers must send summary updates of their income and expenses to HMRC every quarter, using MTD-compatible software. This is in addition to a final end-of-period statement and a final declaration (replacing the annual self-assessment return).

Does MTD for Income Tax replace self-assessment?

Effectively, yes. The quarterly updates and final declaration process replaces the traditional annual self-assessment return for those within scope. The process moves from one annual submission to four quarterly updates plus a final declaration.

How should accounting firms prepare?

Start now: audit your client base to identify who is affected, confirm your software supports MTD for ITSA, migrate clients to digital bookkeeping, build quarterly workflows, train your team, and communicate changes to clients well before the deadline.

What happens if clients are not ready by April 2026?

HMRC is expected to apply penalties for non-compliance, similar to the points-based penalty system used for MTD for VAT. The best approach is to prepare well ahead rather than risk last-minute scrambles.

Need help preparing your firm for MTD?

Book a free discovery call to discuss your MTD readiness and get a personalised preparation plan.

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