Dont Panic – Here’s what to do If you missed the tax deadline

So… You Missed the Deadline?

Breathe. You’re not the first — and you definitely won’t be the last.

Every year, thousands of UK business owners, side-hustlers, and self-employed folks miss the tax return deadline. Life happens. Maybe it slipped your mind, maybe the paperwork was a mess, maybe you thought your accountant had it covered.

Whatever the reason, here’s the important bit:

You can still fix this.
And we’re going to show you how — without jargon, judgement, or unnecessary panic.

Quick Reminder: When Are the UK Tax Deadlines?
For Self Assessment:

• 31 January — Deadline to file your online tax return
• 31 January — Deadline to pay your tax bill
• Late by 1 day? You’re already racking up penalties.
• Late by 3 months? It gets worse.

What Happens If You Missed It?
If You’re Just a Little Bit Late (Up to 3 Months):

• £100 penalty – Flat fine from HMRC for missing the deadline
• No excuses unless you have a valid “reasonable excuse” (more on that below)

If You’re 3–6 Months Late:

• £100 penalty + daily fines
• £10 per day for up to 90 days (yes, that’s £900!)
• Total fine: £1,000+ and rising

If You’re Over 6 Months Late:

• Extra penalties: 5% of the tax you owe
• HMRC may estimate your tax bill and start collection action

And the worst part?
The longer you leave it, the more painful (and expensive) it gets.

Step-by-Step: What to Do Now

1. Don’t Ignore It

Seriously. Ignoring HMRC is the worst option.
They won’t forget — and they’ll happily add interest, penalties, and start chasing you.

2. Get Your Paperwork Together

Start gathering your income records, expenses, bank statements, and anything else related to your business for the tax year.

Even if it’s messy or incomplete — start now.
You don’t need perfection, you need progress.

3. Submit Your Return ASAP

Even if you can’t pay your bill yet, it’s better to file your return first. That stops the late filing penalties from growing.

You can deal with the payment after filing — HMRC allows time-to-pay arrangements (more below).

4. Can’t Pay? Set Up a Payment Plan

HMRC isn’t evil. If you’re upfront, they’ll usually let you spread the cost.

Use HMRC’s “Time to Pay” service:
You can apply online (if your bill is under £30,000), or call them if you need something tailored.

5. Check If You Have a Valid Excuse

HMRC might cancel your penalty if you had a “reasonable excuse” — such as:

• Serious illness or hospital stay
• Bereavement
• Fire or flood at your premises
• HMRC online services were down
• You relied on someone else who let you down (e.g. accountant error — sometimes)

But you’ll need to prove it. No, “I forgot” or “I was busy” won’t cut it.

6. Still Not Sure? Ask for Help

A good accountant can help you:

• File quickly
• Reduce penalties
• Negotiate with HMRC
• Make sure your return is done right
• Spot any overpaid tax or missed claims

And if you’ve done multiple years late (yes, it happens!), they’ll help you clean up the whole mess.

Missing the Deadline Doesn’t Mean You’re Doomed
You’re not a criminal. You’re not the only one. And you’re definitely not beyond help.

The key is to act now — not next week, not next month. The sooner you file, the less you’ll pay.

Need Help? We’ve Got You Covered
We don’t judge — we help to sort it (with our partners’ help)

Whether you’re:

• One day late
• Three months late
• Or haven’t filed in years…

We’ll help you get back on track, deal with HMRC, and avoid future stress.