Understanding the MTD ITSA Quarterly Update Schedule
One of the most common misconceptions about Making Tax Digital for Income Tax Self Assessment (MTD ITSA) is the number of returns required. People often ask:
“Do I really have to file my tax return four times a year?”
The answer? Not exactly. Under MTD ITSA, you’ll need to send quarterly updates to HMRC — but these are not full tax returns.
In this post, we’ll explain:
- What the quarterly updates are
- When you need to submit them
- What information you must include
- How Merranti Accounting makes it simple to stay on track
What Are Quarterly Updates Under MTD ITSA?
Starting from April 2026, most self-employed individuals and landlords earning over £50,000 will be required to:
-
Keep digital records of income and expenses.
-
Submit quarterly updates to HMRC for each source of income.
-
File a year-end final declaration (a replacement for the current Self Assessment).
So, instead of one Self Assessment per year, you’ll submit:
- 4 quarterly updates (summaries)
- 1 final declaration
Quarterly Updates vs. Tax Returns: What’s the Difference?
| Feature | Quarterly Update | Final Declaration (Year-End) |
|---|---|---|
| Purpose | Reports income & expenses to HMRC | Confirms full tax position |
| Level of Detail | Summary only (categories, totals) | Detailed (includes all income) |
| Includes other income? | ❌ No (only property/self-employment) | ✅ Yes (e.g. dividends, pensions) |
| Tax calculated? | ❌ No – estimates only | ✅ Yes – final tax bill calculated |
| Client approval? | ❌ Not required | ✅ Required (under PCRT rules) |
You are not doing four tax returns. You are submitting four sets of summarised figures to HMRC — much simpler and quicker than a full return.
The Quarterly Update Periods
Under MTD ITSA, updates follow a standard calendar quarter unless you choose otherwise. The default quarters are:
| Quarter | Period Covered | Submission Deadline |
|---|---|---|
| Q1 | 6 April – 5 July | 5 August |
| Q2 | 6 July – 5 October | 5 November |
| Q3 | 6 October – 5 January | 5 February |
| Q4 | 6 January – 5 April | 5 May |
HMRC allows you to elect calendar quarters instead — this means your quarters run as:
- 1 Apr – 30 Jun
- 1 Jul – 30 Sep
- 1 Oct – 31 Dec
- 1 Jan – 31 Mar
We recommend this calendar-based option for simplicity — and we’ll help you set it up.
What Information Must Be Included?
Quarterly updates require totals for each category of income and expense for your self-employment or property business.
Examples:
- Income
- Sales or rental receipts
- Any rebates or other income
- Expenses
- Rent
- Repairs and maintenance
- Travel
- Utilities
- Insurance
- Accountancy fees
You don’t need to attach receipts or give item-by-item details — just accurate summaries based on your digital records.
Do I Need to Submit for Each Income Type?
Yes. If you have:
- 2 self-employed businesses
- 2 rental properties
- 1 of each
You must submit a separate update for each source — meaning potentially more than 4 updates per year.
At Merranti Accounting, we consolidate all this behind the scenes so you don’t have to worry about duplication or confusion.
What Happens If I Miss a Deadline?
Under the new HMRC points-based penalty system, missing quarterly deadlines can result in:
- 1 penalty point per missed update
- A £200 penalty once you reach 4 points
- Points reset after 24 months of compliance
In addition, there may be late submission penalties of up to £3,000 per quarter in serious non-compliance cases.
What Happens at the End of the Year?
Once all four updates are submitted, you’ll file a final declaration which:
- Pulls together your year-end position
- Includes other income (employment, dividends, pensions)
- Triggers the final tax calculation
- Requires your approval before submission
This replaces the traditional Self Assessment and becomes your official tax return under MTD.
How Merranti Makes Quarterly Updates Easy
1. Simple Software Setup
We’ll help you install and learn Xero, QuickBooks, or a spreadsheet + bridging solution — all of which support direct quarterly submissions.
2. Automated Reminders
Our system and AI assistant Martin will notify you when each quarter ends and what’s needed for submission.
3. Digital Record Support
We’ll check your receipts and records (via Hubdoc or your preferred method) and ensure everything is up to date.
4. Quarterly Review
Before anything goes to HMRC, we’ll double-check your income/expense figures, correct errors, and submit on your behalf.
5. Final Declaration Assistance
At year-end, we’ll compile your complete tax profile and ensure your final declaration is accurate and signed off.
Special Offer: Get Your Quarterly System Set Up for Free
We’re currently offering a free MTD readiness call to:
- Review your income types and thresholds
- Recommend the best record-keeping method
- Set up your software
- Plan your quarterly submission calendar
Summary: What You Need to Know
- You’ll submit quarterly updates of summarised income/expenses
- You can choose calendar or tax quarters
- Submissions are due one month after each quarter
- These updates are not full tax returns
- A final declaration is still required annually
- Penalties apply for missed submissions — so don’t leave it to chance!
Final Thought
MTD ITSA may seem like extra admin, but with the right tools and team, it can actually simplify how you manage your business finances.
At Merranti Accounting, we don’t just provide software — we provide support, training, and hands-on guidance to make MTD as stress-free as possible.
Let’s make tax work for you — not against you.
📞 Need help staying on track with quarterly updates?
Find more about MTD ITSA here
