What Happens If You Miss Your MTD Deadline: Penalties and How to Appeal

Missing an MTD deadline is not the end of the world, but it is not consequence-free either. HMRC has introduced a new points-based penalty system for MTD that works differently from the old fixed-penalty approach to Self Assessment. Understanding how it works — and what to do if you miss a deadline — could save you hundreds of pounds.

How the New Penalty Points System Works

From April 2026, HMRC is replacing the old fixed-penalty system with a points-based approach for late submissions. Here is how it works:

Earning points: Each time you submit a quarterly update or final declaration late, you receive one penalty point. It does not matter whether you are one day late or one month late — you get one point regardless.

Reaching the threshold: For quarterly obligations (which is what most MTD taxpayers have), the penalty threshold is 4 points. Once you reach 4 points, every subsequent late submission triggers an automatic £200 penalty.

Resetting points: Points do not last forever. You can reset your points to zero by meeting all your submission deadlines for a continuous 24-month period (for quarterly obligations). This gives you an incentive to get back on track rather than giving up.

Late Submission Penalties in Practice

Here is a practical example of how the system works over two years:

| Submission | On time? | Points total | Penalty? | |------------|----------|-------------|----------| | Q1 2026/27 | Late | 1 | No | | Q2 2026/27 | On time | 1 | No | | Q3 2026/27 | Late | 2 | No | | Q4 2026/27 | On time | 2 | No | | Final declaration | On time | 2 | No | | Q1 2027/28 | Late | 3 | No | | Q2 2027/28 | Late | 4 | No — but threshold reached | | Q3 2027/28 | Late | 4 | £200 penalty | | Q4 2027/28 | Late | 4 | £200 penalty |

As you can see, occasional lateness does not immediately cost you money. But once you hit the threshold, every late submission becomes expensive.

Late Payment Penalties

Separately from late submission penalties, there are penalties for paying your tax late:

• Days 1–15 late: No penalty, but interest is charged from day one at the Bank of England base rate plus 2.5%
• 16–30 days late: A penalty of 2% of the tax outstanding at day 15
• 31 days or more late: An additional 2% of the tax outstanding at day 30
• Over 6 months late: A further penalty calculated daily at 4% per annum of the outstanding amount

These penalties stack, so being significantly late on a large tax bill can become very costly very quickly.

What Counts as a Reasonable Excuse?

HMRC recognises that sometimes there are genuine reasons for missing a deadline. If you have a reasonable excuse, you can appeal a penalty and may have it cancelled.

Reasonable excuses that HMRC typically accepts:

• Serious illness or hospitalisation — either yours or a close family member's, where it genuinely prevented you from meeting the deadline
• Bereavement — the death of a close family member or partner near the deadline
• Fire, flood, or other disaster — damage to your home or business premises that prevented you from accessing your records
• HMRC service issues — if HMRC's online systems were down or unavailable when you tried to submit
• Postal delays (for paper submissions) — though this is less relevant for MTD digital submissions
• Unexpected hospital stay — where you were unable to arrange for someone else to handle the submission

Reasonable excuses that HMRC typically does not accept:

• Forgetting the deadline
• Being too busy with work
• Not understanding the rules
• Your accountant made a mistake (though this may be a complaint against your accountant)
• Computer problems or software issues (unless it was your MTD software provider's fault)
• Finding the process confusing
• Not having the money to pay (this is not an excuse for late submission, though it may support a Time to Pay arrangement)

How to Appeal a Penalty

If you receive a penalty and believe you have a reasonable excuse, you can appeal:

Step 1: Gather Your Evidence

Before appealing, collect evidence supporting your reasonable excuse:

• Medical certificates or hospital records for illness
• Death certificates for bereavement
• Insurance claims or photographs for fire or flood damage
• Screenshots of error messages if HMRC systems were down
• Correspondence showing any postal issues

Step 2: Appeal Online or By Post

You can appeal an MTD penalty through:

• Your Government Gateway account — this is the quickest method
• By post — write to the address on your penalty notice

Your appeal should include:

• Your name and UTR (Unique Taxpayer Reference)
• The penalty reference number
• The reason for your appeal (your reasonable excuse)
• Supporting evidence
• The dates you were affected

Step 3: Submit As Soon As Possible

You have 30 days from the date of the penalty notice to appeal. If you miss this window, you can still make a late appeal, but you will need to explain why the appeal itself is late.

Step 4: Wait for HMRC's Decision

HMRC will review your appeal and respond in writing. They may:

• Accept your appeal and cancel the penalty
• Reject your appeal and uphold the penalty
• Ask for more information before making a decision

Step 5: Escalate If Necessary

If HMRC rejects your appeal and you disagree, you can:

• Request a statutory review by a different HMRC officer
• Appeal to the First-tier Tribunal (Tax) — an independent tribunal that hears tax disputes

Most disputes are resolved at the review stage, but the tribunal is available as a last resort.

How to Avoid Penalties in the First Place

The best strategy is prevention. Here are practical steps to ensure you never miss an MTD deadline:

Use software with automatic reminders. Good MTD software notifies you well before each deadline. Accounted sends reminders and can even auto-submit your quarterly updates once you have reviewed them.

Keep records up to date weekly. If your records are current, submitting a quarterly update takes minutes. The people who miss deadlines are usually the ones who leave everything to the last minute.

Set up bank feeds. Automatic transaction import means your records are always up to date without manual effort.

Use calendar reminders. Set reminders for two weeks before, one week before, and the day before each deadline.

Delegate to your accountant. If you struggle with deadlines, your accountant can manage your MTD submissions through their agent account.

Submit early. There is no requirement to wait until the deadline. Submit as soon as the quarter ends and your records are complete.

What to Do If You Have Already Missed a Deadline

If you have already missed an MTD deadline, here is what to do:

1. Submit as soon as possible. Even though you have missed the deadline, submit your update immediately. Do not wait until the next quarter.
2. Check your penalty points. Log into your Government Gateway account to see how many points you have accumulated.
3. Consider an appeal. If you have a genuine reasonable excuse, appeal the penalty point within 30 days.
4. Set up systems to prevent it happening again. If this was your first late submission, you have time to fix your processes before you reach the penalty threshold.
5. Pay any tax owed promptly. Late payment penalties are separate from late submission penalties. Pay as soon as you can to minimise interest charges.

The Bigger Picture

HMRC's penalty system is designed to encourage compliance, not to punish occasional mistakes. The points system gives you a buffer — you can be late a few times without financial penalties, as long as you get back on track.

The taxpayers who will be hit hardest are those who persistently ignore their obligations. If you are reading this guide and thinking about how to stay compliant, you are already ahead of the curve.

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