Many small businesses in Birmingham, Wolverhampton, and across the West Midlands get penalised simply due to missed deadlines. HMRC doesn't send reminders — it's your responsibility to file and pay on time.
Missing a deadline costs a minimum of £100 immediately, plus interest on any unpaid tax. For many businesses, it's avoidable stress and wasted money.
- 31 January: Self Assessment deadline (file + pay)
- Quarterly: VAT returns (1 month + 7 days after period end)
- 9 months after year-end: Corporation Tax payment
- 19th of every month: PAYE payment (if you have employees)
- Miss any of these = £100+ penalty + interest
Self Assessment Tax Return Deadlines
If you're self-employed, a director, a landlord, or have income over £100,000, you must file a Self Assessment tax return.
Key Dates:
| Date | Deadline | Penalty if Late |
|---|---|---|
| 5 October 2026 | Register for Self Assessment (if new) | £100+ |
| 31 October 2026 | Paper return deadline | £100 |
| 31 January 2027 | Online return + payment deadline | £100 + daily penalties |
| 31 July 2027 | Second payment on account | Interest charges |
What is "payment on account"?
If you owe over £1,000 in tax, HMRC requires you to pay tax in advance for the next year. You make two payments:
- 31 January: First payment (50% of last year's tax bill)
- 31 July: Second payment (remaining 50%)
- 31 January (following year): Balancing payment + first payment for new year
Full guide: Self Assessment Compliance: Avoid Costly Errors
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If you're VAT registered, you must submit returns quarterly (or monthly if you've opted in).
Standard VAT Quarters (Most Common):
| Quarter Ending | Deadline |
|---|---|
| 31 March | 7 May |
| 30 June | 7 August |
| 30 September | 7 November |
| 31 December | 7 February (following year) |
Important: VAT deadlines are 1 month + 7 days after the end of your VAT period.
All VAT returns must be submitted electronically via Making Tax Digital (MTD) for VAT. Paper submissions are no longer accepted.
Full guide: VAT Compliance: Common Mistakes That Cost Businesses Money
Corporation Tax Deadlines
If you run a limited company, you must file a Corporation Tax return (CT600) and pay Corporation Tax.
Key Deadlines:
- 9 months after year-end: Corporation Tax payment deadline
- 12 months after year-end: CT600 return filing deadline
Example:
- Company year-end: 31 March 2026
- Payment deadline: 1 January 2027 (9 months later)
- Filing deadline: 31 March 2027 (12 months later)
Pro Tip: Pay Corporation Tax early if you can. Interest rates on late payments are high (currently 7.75% per year).
Want to reduce your Corporation Tax bill legally? Use our free calculator to estimate potential savings.
Full guide: Corporation Tax Compliance Explained (UK 2026)
PAYE & Payroll Deadlines
If you employ staff (including yourself as a director taking a salary), you must operate PAYE.
Monthly Deadlines:
- 19th of every month: PAYE payment deadline (by post)
- 22nd of every month: PAYE payment deadline (electronic payment)
- Before/on payday: Submit Full Payment Submission (FPS) to HMRC
Annual Deadlines:
- 19 May: P60s issued to all employees (for previous tax year)
- 6 July: P11D forms submitted to HMRC (for benefits in kind)
- 19 July: Class 1A National Insurance payment (on P11D benefits)
Most West Midlands businesses use payroll software to automate these submissions. If you're still doing payroll manually, you're at high risk of missing deadlines.
Making Tax Digital (MTD) Deadlines
From April 2026, Making Tax Digital for Income Tax becomes mandatory for sole traders and landlords with income over £50,000.
MTD Quarterly Deadlines:
You must submit quarterly updates to HMRC:
- Quarter 1 (6 Apr - 5 Jul): Deadline 5 August
- Quarter 2 (6 Jul - 5 Oct): Deadline 5 November
- Quarter 3 (6 Oct - 5 Jan): Deadline 5 February
- Quarter 4 (6 Jan - 5 Apr): Deadline 5 May
Plus a final declaration by 31 January following the tax year end.
Full guide: Making Tax Digital: What You Must Do Before April 2026
Penalty Costs (What Happens If You're Late)
- 1 day late: £100 fixed penalty
- 3 months late: Additional £10 per day (max £900)
- 6 months late: £300 or 5% of tax due (whichever is higher)
- 12 months late: Another £300 or 5% of tax due
- 30 days late: 5% of unpaid tax
- 6 months late: Additional 5% of unpaid tax
- 12 months late: Another 5% of unpaid tax
- Plus: Interest charged from deadline (currently 7.75% per year)
Example: Miss the 31 January Self Assessment deadline by 4 months with £5,000 tax due:
- £100 fixed penalty
- £900 daily penalties (£10 x 90 days)
- £250 interest (approx, 4 months at 7.75%)
- Total cost: £1,250 in penalties + interest
This is money wasted. For a fraction of that cost, you could work with an accountant who ensures you never miss a deadline.
Full guide: HMRC Penalties Explained: How to Avoid Them
How to Never Miss a Deadline
Option 1: Calendar Reminders
Set recurring calendar reminders 2 weeks before every deadline:
- 15 January: Self Assessment reminder
- 7th of month after VAT quarter: VAT reminder
- 3 months before year-end + 9 months: Corporation Tax payment reminder
Option 2: Use Accounting Software
Software like Xero, QuickBooks, or FreeAgent tracks deadlines for you and sends automatic reminders.
Option 3: Work with an Accountant
At Brightson Accounting, we track all deadlines for our clients. You don't have to remember dates — we handle filing and remind you when payments are due.
Most of our Wolverhampton and West Midlands clients never think about deadlines because we manage compliance for them.
Deadline Checklist (Print This)
- 5 Oct 2026: Register for Self Assessment (if new)
- 31 Oct 2026: Paper Self Assessment deadline
- 31 Jan 2027: Online Self Assessment + payment
- Quarterly: VAT returns (1 month + 7 days after quarter)
- 19th monthly: PAYE payment
- 9 months after year-end: Corporation Tax payment
- 12 months after year-end: CT600 filing
Want help staying on top of these deadlines? Speak to an accountant who specialises in compliance.
Final Thoughts
HMRC deadlines are not negotiable. They don't send reminders. And penalties add up fast.
The good news? With basic organisation (or an accountant), you'll never miss a deadline.
The businesses that get penalised are those who:
- Leave everything until the last minute
- Don't track deadlines
- Try to manage compliance alone without systems
Don't be one of them.
🚀 Ready to stay compliant and reduce your tax bill?
We help businesses across Wolverhampton and the West Midlands:
- Stay compliant with HMRC
- Reduce tax legally
- Avoid penalties and investigations