Best Making Tax Digital Software for Accounting Firms in June 2026

April 2026 brings MTD for Income Tax Self Assessment, and your MTD for VAT software probably wasn't designed for what's coming. You'll go from managing one quarterly submission per VAT client to managing four quarterly updates plus end-of-period statements per sole trader and landlord. That's a different workload, a different client base, and a different set of software requirements. The best making tax digital software for accounting firms in 2026 handles MTD for ITSA submissions at scale, works alongside making tax digital bridging software when clients refuse to leave Excel, and covers property income and trading income without forcing you into separate workflows. We'll walk through what qualifies as making tax digital compliant software under HMRC's rules, which making tax digital software UK providers support multi-client ITSA before the threshold drops, what making tax digital software free options actually cover, and where tools like Xero making tax digital and making tax digital bridging software for Sage fit into a firm managing fifty-plus clients across MTD for VAT and MTD for ITSA simultaneously.

TLDR:

• MTD for Income Tax Self Assessment mandates quarterly digital submissions for sole traders and landlords earning above £50,000 from April 2026, dropping to £30,000 in 2027 and £20,000 in 2028.
• HMRC requires a complete digital link from source records to submission with no manual re-keying allowed, which breaks most Excel-to-submission workflows firms currently use.
• Full accounting software handles MTD submissions natively, while bridging software connects spreadsheets to HMRC's API without forcing you to change how you work.
• Free MTD tools cap submissions at one or two VAT entities and rarely cover MTD for ITSA, making them impractical for firms managing multiple clients.
• Tofu processes invoices, receipts, and bank statements before they reach your accounting software, keeping the digital link intact and your MTD submissions backed by source documents from the start.

What is Making Tax Digital software and who needs it

Making Tax Digital (MTD) software is HMRC-approved tech that lets individuals and businesses submit tax records directly to HMRC in a digital format. Instead of filing paper returns or manually entering figures into HMRC's portal, MTD-compliant software keeps digital records and sends them through an API connection that HMRC recognises.

Who actually needs it depends on which MTD phase applies to you:

• VAT-registered businesses above the £90,000 threshold have been required to use MTD for VAT software since 2019, with voluntary sign-up available for those below the threshold.
• Sole traders and landlords with qualifying income above £50,000 must comply from April 2026, dropping to £30,000 from April 2027.
• Smaller sole traders and landlords earning above £20,000 are expected to follow from April 2028.

For accounting firms, the practical question is less about whether clients qualify and more about which software handles multiple client types without creating separate workflows for each. A sole trader, a VAT-registered limited company, and a landlord all have different filing obligations under MTD, and the software your firm picks needs to cover all three without requiring you to manage three separate tools.

Making Tax Digital for Income Tax timelines and thresholds

HMRC is rolling out MTD for Income Tax Self Assessment (ITSA) in phases, with thresholds tied to qualifying income from self-employment and property. HMRC's official guidance sets out exactly who needs to comply and when.

Here is how the schedule currently stands:

April 2026

Sole traders and landlords with qualifying income above £50,000 must comply. This is the first mandatory wave, and HMRC expects the majority of affected taxpayers to already be using MTD-compatible software by this point.

April 2027

The threshold drops to £30,000, bringing a much larger group of sole traders and landlords into scope.

April 2028

The threshold drops again to £20,000, which HMRC projects will cover the vast majority of sole traders and property landlords across the UK.

Qualifying income counts gross income before expenses, so many landlords and sole traders who assume they fall below the threshold may find themselves in scope once their figures are calculated correctly. Partnerships are not yet confirmed for mandation, though HMRC has signalled this is under review.

HMRC software functional requirements for MTD compliance

HMRC sets out specific functional requirements that MTD-compatible software must meet before it can be listed on the gov.uk approved software register. Understanding these requirements helps accounting firms judge whether a given tool will hold up under scrutiny.

There are three core capabilities any MTD-compliant software must have:

• It must connect directly to HMRC's APIs, allowing the software to send and receive data without requiring manual intervention at the submission stage.
• It must maintain a digital link between the source data and the final submission, meaning no manual re-keying of figures between systems is permitted under MTD rules.
• It must store records digitally for the required retention period, which is currently six years for VAT and five years for Income Tax Self Assessment.

What "digital links" actually means in practice

A digital link is any transfer of data between software programs, products, or applications that does not involve a human manually copying or typing figures. Copy-and-paste counts as a broken digital link under HMRC's rules. A formula-linked spreadsheet cell, an automated CSV import, or an API connection all qualify.

This is where many firms get caught out. A firm might use Excel to track client income, then type those totals into a separate submission tool. That workflow fails the digital link requirement regardless of whether the final submission tool itself is HMRC-approved. The entire chain from source record to submission must be digitally linked.

Bridging software as a compliant workaround

Bridging software exists to close this gap. It connects non-MTD-native tools, most commonly Excel spreadsheets, to HMRC's APIs via a compliant digital link. The spreadsheet data is read programmatically instead of re-typed, satisfying the digital link rule while letting firms keep familiar workflows intact.

Types of MTD software: full accounting vs bridging solutions

There are two broad categories of MTD-compatible software, and choosing the wrong one can create more work than it saves.

Full accounting software like Xero, QuickBooks, or Sage handles your entire bookkeeping workflow and submits VAT returns to HMRC directly. If you're already on one of these, MTD compliance is largely built in.

Bridging software takes a different approach. It sits between your existing spreadsheets or legacy system and HMRC's API, converting your data into a compliant submission without forcing you to change how you work. This suits firms or landlords who manage records in Excel and want to stay there.

Here is how the two compare across the decisions that matter most:

Bridging tools are worth considering if your clients are landlords or sole traders who file straightforward returns. Full accounting software makes more sense when you need audit trails, multi-client management, or are preparing for MTD for Income Tax Self Assessment ahead of the 2026 rollout.

Free MTD software options and their limitations

HMRC recognises a handful of free or low-cost options for MTD compliance, but each comes with trade-offs worth understanding before you commit.

Free tools generally fall into two camps: HMRC's own free filing service and third-party bridging software that connects spreadsheets to HMRC's API.

HMRC's free MTD filing service

HMRC offers a basic free service for MTD for VAT and, in limited form, for MTD for Income Tax Self Assessment (ITSA). It covers sole traders and landlords with straightforward affairs, but it was not built for accounting firms managing multiple clients. You cannot file on behalf of clients through the free service without an agent services account and compatible software sitting in front of it.

Free bridging software

Bridging tools let you keep your existing Excel or CSV records and submit the required digital data to HMRC from them. Several providers offer free tiers:

• Most free bridging tools cap submissions at one or two VAT entities, making them impractical for firms with even a modest client portfolio.
• Free tiers rarely cover MTD for ITSA, which becomes mandatory for sole traders and landlords earning above £50,000 from April 2026, dropping to £30,000 a year later.
• Support is typically limited to documentation; there is no live help when a submission fails hours before a deadline.

The real cost of free

The time spent formatting spreadsheets, troubleshooting API rejections, and manually checking submissions across clients tends to outweigh any licence saving fairly quickly. Free MTD software can work for a sole trader filing their own returns, but for an accounting firm, the overhead often makes paid software the cheaper option in practice.

MTD for VAT vs MTD for Income Tax: what accounting firms need to know

MTD for VAT has been live since 2019, so most accounting firms have already worked through the basics. MTD for Income Tax Self Assessment (ITSA) is the expansion that changes the workload substantially.

Under MTD for VAT, VAT-registered businesses submit returns digitally using HMRC-compatible software. The requirement is quarterly, and the data must flow through a digital link from source records to submission.

MTD for ITSA applies to sole traders and landlords with qualifying income above £50,000 from April 2026, dropping to £30,000 from April 2027. Instead of one annual Self Assessment return, affected clients will submit quarterly updates plus a final end-of-period statement each year.

For accounting firms, the practical difference matters:

• MTD for VAT means one quarterly submission per VAT-registered client, with a relatively fixed scope per engagement.
• MTD for ITSA means four quarterly updates per client per year, plus year-end statements, across a much larger client base than VAT alone ever touched. Landlords with property income, in particular, represent a segment many firms have not previously needed to bring into quarterly reporting cycles.

The software requirements differ too. VAT bridging software can satisfy MTD for VAT in many cases, connecting spreadsheets to HMRC via a digital link. MTD for ITSA requires software that can categorise property and trading income, and cumulative quarterly submissions, which rules out basic bridging tools for most ITSA use cases.

Firms preparing now should map their client base against both thresholds, identify which clients will be caught in 2026 versus 2027, and check whether their current software handles ITSA submissions before those deadlines arrive.

Choosing MTD software for accounting firms managing multiple clients

Accounting firms managing multiple clients need MTD software that does more than file a single VAT return. The requirements multiply quickly across a client portfolio, and the wrong choice creates bottlenecks that compound each billing cycle.

There are a few areas worth checking before committing to any software:

• Multi-client management: look for a dashboard that shows submission status across all clients at once, not one where you log in and out of separate accounts to check progress.
• Bridging software compatibility: if clients are still working from spreadsheets, the software needs to read and submit that data without requiring a full migration.
• Pricing structure: per-client pricing adds up fast. Flat monthly fees or unlimited-client tiers are worth prioritising for firms with growing rosters.
• HMRC recognition: the software must appear on HMRC's list of compatible products for the relevant tax type, whether VAT, Income Tax, or both.
• Support quality: MTD deadlines are fixed. If something breaks on a filing day, you need a support team that responds in hours, not days.

No single piece of software will suit every firm equally. The right choice depends on how many clients you manage, what accounting software those clients already use, and how much manual data handling your team currently absorbs each month.

Common MTD software implementation challenges for UK accounting practices

UK accounting practices run into a few recurring problems when rolling out MTD software, and knowing them in advance saves a lot of pain.

Here are the most common ones to watch for:

• Data migration from legacy systems like Sage Desktop or older Excel-based workflows often creates gaps in historical records, particularly when VAT periods straddle the switchover date.
• Staff training takes longer than expected because MTD-compliant tools vary widely in how they handle bridging, submissions, and client portals.
• Client communication gaps lead to missed deadlines when sole traders or landlords don't understand their own obligations under MTD for ITSA.
• Software compatibility issues arise when a practice uses multiple tools that don't share data cleanly, forcing manual reconciliation between systems.

Rushing the rollout without a phased plan is where most practices lose time.

How Tofu simplifies document processing for MTD-ready accounting firms

Tofu sits upstream of your accounting software, handling the document processing work that MTD compliance depends on before anything reaches your ledger. Upload invoices, receipts, and bank statements in any format, and Tofu extracts every line item, maps it to your chart of accounts, and publishes directly to Xero or other connected software. No manual re-keying, no bridging workarounds.

For firms managing MTD submissions across multiple clients, that upstream layer matters. Each client's documents get processed, coded, and published with the account mappings Tofu has learned from your history, so your team reviews instead of re-entering.

Where Tofu fits in an MTD workflow

Tofu handles the step that most MTD software skips: getting source documents accurately into your ledger in the first place. MTD-compliant software can only submit what's already in your records. If those records were built through manual data entry, the compliance layer is only as accurate as the typing that came before it.

• Tofu reads documents in 200+ languages and formats, including handwritten documents, without needing per-document credits or manual template setup.
• Account codes are applied automatically based on what Tofu has learned from your firm's coding history, reducing review time per document as the system builds familiarity with each client.
• Published records feed directly into your connected accounting software, keeping the audit trail clean and your MTD submissions backed by source documents from the start.

Tofu works alongside your existing MTD software instead of replacing it. The document processing layer and the compliance submission layer each do what they were built for.

Final Thoughts on MTD Software Selection

Most MTD software focuses on the submission layer, but that only matters if your records are accurate before you hit submit. The firms that handle MTD without adding headcount are the ones that fixed the document processing step first. Upload a messy bank statement and see how Tofu handles the extraction and coding work that sits upstream of your MTD filing software.

FAQ

What is the best free software for making tax digital?

HMRC offers a basic free MTD filing service for VAT and limited ITSA submissions, but it's built for individuals filing their own returns, not accounting firms managing multiple clients. Free bridging tools exist but typically cap submissions at one or two entities and rarely cover MTD for ITSA, which becomes mandatory from April 2026. For accounting firms, the time spent troubleshooting submissions and formatting spreadsheets usually outweighs any licence saving within the first few months.

MTD for VAT vs MTD for ITSA: what's the actual workload difference?

MTD for VAT means one quarterly submission per VAT-registered client with a relatively fixed scope per engagement. MTD for ITSA means four quarterly updates plus a year-end statement per client, across a much larger client base than VAT alone. Landlords and sole traders represent a segment many firms haven't previously brought into quarterly reporting cycles, and the software requirements differ: basic VAT bridging tools won't handle ITSA's income categorisation and cumulative quarterly submission requirements.

Can I use bridging software for making tax digital without changing my spreadsheets?

Yes. Bridging software connects your existing Excel or CSV records to HMRC's API via a compliant digital link, letting you keep familiar workflows intact while satisfying MTD requirements. The spreadsheet data is read programmatically instead of re-typed, meeting the digital link rule. This works for landlords or sole traders filing straightforward returns, but full accounting software makes more sense when you need audit trails, multi-client management, or are preparing for MTD for ITSA's 2026 rollout.

How does Tofu fit into an MTD-compliant workflow?

Tofu handles the document processing step before anything reaches your MTD software. Upload invoices, receipts, and bank statements in any format. Tofu extracts every line item, maps it to your chart of accounts, and publishes directly to Xero or other connected accounting software. MTD-compliant software can only submit what's already in your records, so Tofu builds those records accurately from source documents before your MTD submission layer takes over.

What are the HMRC software functional requirements for making tax digital?

HMRC requires three core capabilities: direct API connection to HMRC for sending and receiving data without manual intervention, a digital link between source data and final submission with no manual re-keying permitted, and digital record storage for the required retention period (six years for VAT, five years for ITSA). A digital link is any automated data transfer: formula-linked spreadsheet cells, CSV imports, or API connections all qualify, but copy-and-paste breaks the digital link under HMRC's rules.