The First Quarterly Deadline Has Passed. Now What?
Today, the 7th of August 2026, marks the first quarterly submission deadline under Making Tax Digital for Income Tax. For the thousands of UK accounting firms that have been preparing their Phase One clients since April, it is a significant milestone. But it is also a moment to look up from the immediate workload and ask a question that will define your practice's position over the next eighteen months: are you ready for what comes next?
Phase Two of MTD for Income Tax takes effect on the 6th of April 2027. From that date, sole traders and landlords with qualifying gross income above £30,000 will be required to keep digital records and submit quarterly updates to HMRC. For most UK accounting practices, this cohort is significantly larger than the Phase One group. The window to prepare them is not as wide as it looks.
Understanding the Scale of Phase Two
The income threshold for Phase One was set at £50,000, which brought a relatively contained group of clients into scope. Phase Two drops that threshold to £30,000, more than doubling the population of affected taxpayers. HMRC estimates that hundreds of thousands of additional sole traders and landlords will enter the MTD regime in April 2027.
For a typical small or mid-sized accounting practice, this means a substantial portion of the client base will need to be onboarded to MTD-compatible workflows within the next eight months. Many of these clients will have lower digital confidence, less sophisticated bookkeeping arrangements, and a greater need for hands-on support than the higher-income Phase One cohort.
The practices that manage this transition well will be those that start their preparation now, not in January 2027.
Why the Timing Is More Urgent Than It Appears
Eight months feels like a comfortable runway. It is not, for two reasons.
First, your practice is simultaneously managing a full quarterly compliance cycle for Phase One clients. The next quarterly submission deadline is the 7 of November 2026, followed by the 7 of February 2027, and then the 7 of May 2027. The quarterly rhythm is now a permanent feature of your workload calendar. Every month between now and April 2027 already has compliance obligations attached to it.
Second, onboarding clients to MTD is not a quick process. For clients who are currently using paper records or basic spreadsheets, the journey involves choosing compatible software, setting up digital records, transferring existing data, obtaining HMRC authorisation, and building new habits around regular data entry. For clients with limited digital confidence, this process can take several months even with active support from their accountant.
If you wait until the new year to begin identifying and onboarding your Phase Two cohort, you will be doing so at the same time as managing the third quarterly submission cycle for Phase One clients, and the pressure will be considerable.
A Practical Roadmap for the Next Eight Months
The following approach gives practices a structured way to manage both the ongoing Phase One workload and the Phase Two preparation in parallel.
August and September 2026: Segment Your Phase Two Cohort
Begin by running a client segmentation exercise using 2025/26 Self Assessment data as it becomes available, alongside existing records. Your goal is to identify every client with qualifying gross income between £30,000 and £50,000, because these clients will be mandatory from April 2027. Qualifying income means gross income from self-employment and UK property combined, before expenses, not profit.
- Flag clients near the £30,000 threshold for monitoring, as income fluctuations could affect their start date.
- Classify each client by their current bookkeeping approach: cloud software, spreadsheet, or paper records.
- Identify clients with limited digital confidence or complex income arrangements who will need the most lead time.
This segmentation exercise is the foundation for everything that follows. Without it, you are designing a preparation programme without knowing the real shape of the problem.
October and November 2026: Begin Client Communications
Once you have a clear picture of your Phase Two cohort, begin structured outreach. The goal at this stage is awareness, not full onboarding. Clients need to understand that MTD will apply to them from April 2027, what that means in practical terms, and what they will need to do to be ready.
A well-designed communication at this stage has several benefits. It positions your practice as proactive and well-informed. It gives clients time to absorb the change before they are asked to act on it. And it creates a natural opening for a conversation about your MTD service offering and pricing.
- Send a personalised letter or email to every Phase Two client confirming their MTD start date.
- Include a plain-language explanation of what quarterly reporting involves and what will change for them.
- Invite clients to a briefing session, whether in person, by phone, or via webinar, where they can ask questions.
December 2026 and January 2027: Software Selection and Onboarding
For clients who are not yet using MTD-compatible software, this is the period to begin the transition. The key decisions at this stage are which software platform is right for each client, and how the practice will support the setup process.
Not every client needs the same solution. A sole trader with straightforward income and expenses has different needs from a landlord with multiple properties and mixed income sources. Practices that offer a curated shortlist of recommended software options, rather than leaving clients to navigate the market alone, will achieve faster and more consistent onboarding outcomes.
TaxCalc's MTD-compatible software is designed to make this process straightforward for practices managing multiple client onboardings simultaneously. With tools built specifically for practice use, including quarterly submission workflows and bridging solutions for clients using spreadsheets, it supports a wide range of client configurations without requiring a different approach for each one.
February and March 2027: Final Readiness Checks
In the final weeks before the April 2027 mandation date, focus on confirming that every Phase Two client is fully set up and ready to submit. This means:
- Digital records are in place and up to date.
- Software is connected and tested.
- HMRC authorisation is confirmed for each client.
- Clients understand what they need to do each quarter and by when.
Any gaps identified at this stage should be treated as urgent. A client who reaches 6 April 2027 without compatible software or digital records in place will be non-compliant from day one, and while a soft landing applied in Year One, there is currently no confirmed equivalent for the Year Two cohort.
Do Not Overlook Phase Three
While Phase Two preparation is the immediate priority, practices should also be building awareness of Phase Three, which takes effect on the 6th of April 2028 and extends MTD to sole traders and landlords with qualifying income above £20,000. This will be the largest single expansion of the MTD regime and will bring many more clients into scope, including those with relatively modest income levels and potentially the least digital readiness of any group yet.
Identifying your Phase Three cohort now, even at a high level, allows you to build awareness into your client communications over the next eighteen months and avoids a repeat of the last-minute scramble that some practices experienced ahead of April 2026.
Turning Preparation Into a Practice Growth Opportunity
There is a commercial dimension to Phase Two preparation that is worth naming directly. Every client you onboard to MTD is a client whose engagement with your practice deepens. Quarterly reporting means quarterly contact, which means more opportunities to deliver value, identify planning opportunities, and strengthen the relationship.
Practices that are proactive in their Phase Two outreach will also find it easier to have the fee conversation. Clients who understand what MTD involves, and who see their accountant taking the lead in managing the transition, are far more receptive to revised pricing than those who are presented with a higher bill without context.
Consider reviewing your service packages now to ensure they reflect the increased workload that quarterly reporting creates. A tiered model that separates core compliance from advisory services gives clients a clear choice and gives your practice a sustainable commercial framework for the MTD era.
How TaxCalc Supports Your MTD Journey
TaxCalc has been supporting UK accounting firms through every stage of the MTD transition. Our software is fully compatible with MTD for Income Tax requirements across all three phases, covering digital record keeping, quarterly submissions, and Final Declarations. Our MTD Quarterly Filer is designed specifically for practice use, allowing you to manage multiple client submissions efficiently from a single platform.
Whether you are consolidating your Phase One workflows, preparing your Phase Two cohort for April 2027, or planning ahead for Phase Three, TaxCalc gives your practice the tools to stay ahead of the curve. Get in touch with our team today to find out how we can support your practice through the next phase of MTD and beyond.
