Submitting your self assessment tax return on time is vital for contractors and freelancers operating through Limited companies. Missing the UK tax return deadlines can lead to significant penalties, interest charges, and even the risk of a tax investigation. Planning ahead will not only save you money but also reduce unnecessary stress.

At Nexus Accounting, we specialise in supporting contractors and freelancers. Below, we’ve outlined what happens if you don’t submit your tax return on time, the penalties you could face, and how our expert team can help you stay compliant.

• When Do I Need to Submit My Tax Return By?
• What Happens If I Don’t Submit My Tax Return on Time?
• Reasonable Excuses for Late Filing or Payment
• Why Contractors & Freelancers Should Be Extra Careful
• How Nexus Accounting Can Help Contractors & Freelancers

When Do I Need to Submit My Tax Return By?

Contractors and freelancers trading through Limited companies need to be aware of the key UK tax return deadlines set by HMRC:

• 31 October – Paper tax return deadline
• 31 January –  Online tax return deadline for the previous tax year
• 31 January –  Payment deadline for any tax owed.

Missing any of these deadlines triggers penalties from HMRC, which can quickly escalate if left unresolved.

What Happens If I Don’t Submit My Tax Return on Time?

If a contractor or freelancer misses the deadline, HMRC automatically issues penalties. There are two main categories:

• Late filing penalties –  if you fail to submit your return.
• Late payment penalties – if you don’t pay the tax you owe on time.

You’ll also be charged interest on both unpaid tax and penalties. Worse still, filing late puts you on HMRC’s radar, increasing the likelihood of a tax enquiry – something every contractor wants to avoid.

Late Filing Penalties

Here’s a breakdown of HMRC’s penalties for late filing of a self assessment tax return:

• Miss filing deadline: £100 penalty.
• 3 months late: Daily penalty of £10 per day for up to 90 days (maximum £900).
• 6 months late: 5% of tax due or £300, whichever is greater.
• 12 months late: 5% of tax due or £300, whichever is greater, unless HMRC believes you are deliberately withholding information.

If HMRC decides the taxpayer deliberately withholds information:

• Deliberate and concealed withholding: 100% of tax due (or £300 if greater).
• Deliberate but not concealed: 70% of tax due (or £300 if greater).

Reductions can apply if you proactively disclose information or cooperate with HMRC.

Late Payment Penalties

In addition to filing penalties, late tax payments also incur charges:

• 30 days late: 5% of tax due.
• 6 months late: Additional 5% of tax still outstanding.
• 12 months late: Another 5% of tax is still outstanding.

On top of this, HMRC charges daily interest until the debt is cleared.

Reasonable Excuses for Late Filing or Payment

If you miss the deadline, HMRC allows you to appeal penalties if you have a reasonable excuse. Examples include:

• HMRC’s online services are not working.
• Serious illness or hospitalisation.
• Bereavement of a close relative.
• Computer/software failure at the time of submission.
• Postal delays beyond your control.
• Disability-related delays.

What HMRC will not accept as reasonable excuses:

• The return was too difficult to complete.
• You were too busy with work.
• Your accountant or adviser missed the deadline.
• HMRC didn’t send you a reminder.
• You didn’t have the funds to pay your tax.

It’s always best practice for contractors and freelancers to plan ahead and file before the deadline to avoid relying on an appeal.

Why Contractors & Freelancers Should Be Extra Careful

Contractors and freelancers working through Limited companies often juggle multiple contracts and expenses, making their self assessment tax return more complex. Any delays or errors not only risk penalties but could also flag issues with IR35 compliance and company expenses, areas HMRC monitors closely.

By missing a deadline, you’re increasing the chance of an HMRC enquiry, which can be time-consuming, stressful, and costly. Filing on time and paying your liabilities promptly keeps you compliant and avoids unnecessary attention.

How Nexus Accounting Can Help Contractors & Freelancers

At Nexus Accounting, we work exclusively with contractors and freelancers operating through Limited companies. We’ll ensure:

• Your self assessment tax return is filed accurately and on time.
• You understand your UK tax return deadlines and set reminders well in advance.
• We manage all HMRC correspondence on your behalf.
• You receive proactive tax planning advice to minimise liabilities.

If you’re worried about late tax return penalties or haven’t yet submitted your return, our expert team is here to help. Contact our expert team for immediate advice.

FAQs on Self Assessment for Contractors & Freelancers

When do I need to submit my tax return?

The online submission deadline is 31 January following the end of the tax year. For example, for the 2025/26 tax year, the deadline is 31 January 2027. Any tax owed must also be paid by this date, so it’s best to prepare in advance rather than waiting until the last minute.

What happens if I don’t submit my tax return on time?

You’ll face automatic late filing penalties starting from £100. If the return is more than three months late, daily penalties apply, and further fines are charged at the six- and twelve-month marks. Interest is also added to unpaid tax, so the longer the delay, the higher the overall cost.

Can I appeal a late filing penalty?

Yes, you can appeal if you have a reasonable excuse, such as serious illness, bereavement, or HMRC system failures that prevented you from filing. However, HMRC takes a strict view of what qualifies, so it’s always safer to file on time rather than relying on an appeal.

Do these penalties apply to contractors and freelancers operating through Limited companies?

Yes. Even if you operate through a Limited company, you may still need to submit a self assessment tax return to declare income such as dividends, rental earnings, or other untaxed income. Contractors and freelancers must meet HMRC deadlines in the same way as any other taxpayer to avoid penalties.

Stay Compliant & Avoid Penalties

Missing your self assessment tax return deadline can be costly and stressful. With Nexus Accounting, contractors and freelancers get peace of mind knowing their returns are handled by experts who understand their unique needs.

Need some more advice? Please fill in our contact form found on our contact page to speak with our experts today.

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