As the Self Assessment deadline looms each year on 31 January, a growing number of taxpayers begin to feel the pressure of meeting their obligations. Whether you’re a seasoned freelancer, a landlord with rental income, or someone with untaxed income from various sources, knowing the rules and timing around tax submissions can help you avoid penalties and manage your finances better.
One common question that arises every January is: will my tax return be deposited at midnight if I file right before the deadline? This query often reflects a deeper uncertainty about the timing of submissions, the consequences of filing or paying late, and how different filing and payment methods affect compliance. This article explores these concerns and helps you navigate the deadline with confidence.
Understanding the Self Assessment System
Self Assessment is HMRC’s method of collecting income tax from individuals whose income isn’t taxed at source. This includes self-employed professionals, business owners, landlords, and others who earn untaxed income. Through the Self Assessment system, you’re responsible for calculating your own tax liability and reporting it to HMRC.
The deadline for filing your Self Assessment tax return and paying any tax owed is 11:59 pm on 31 January for the tax year ending the previous 5 April. For example, for the tax year running from 6 April 2023 to 5 April 2024, the online filing and payment deadline is 31 January 2025.
Why the Deadline Matters
Missing the Self Assessment deadline comes with automatic penalties. The moment the clock ticks past midnight on 31 January, a £100 late filing penalty is applied. This applies even if you don’t owe any tax or if your tax return is only a few minutes late.
More penalties follow the longer you delay. After three months, daily penalties begin accruing. By six and twelve months, further fixed or percentage-based penalties can be applied. If you miss the payment deadline as well, interest starts accruing from 1 February, increasing your liability over time.
Can You Submit at Midnight?
Technically, yes. HMRC’s online system remains open right up until 11:59 pm on the deadline day. If your return is successfully submitted and acknowledged by HMRC before midnight, it counts as on time. This is why some taxpayers choose to file in the final hour.
However, this approach is not without risks. HMRC’s system experiences high traffic on deadline day. The website may slow down or temporarily crash. Login issues or two-factor authentication delays could cause you to miss the deadline altogether. Any technical difficulties occurring near midnight can turn a last-minute filing attempt into a costly mistake.
How to File Your Self Assessment Return
There are three main ways to submit your Self Assessment tax return. Each option comes with its own advantages and potential challenges depending on your level of tax knowledge, complexity of your finances, and how close you are to the deadline.
Filing through HMRC’s Online Portal
This is the standard method for most individuals. Once you’ve registered for Self Assessment and set up your Government Gateway account, you can log in, fill out the required sections, and submit your return online. You’ll receive an immediate submission receipt.
This method is cost-effective and suitable for straightforward tax situations. However, it requires you to do all the calculations yourself. Mistakes are more likely if you’re unfamiliar with tax rules or uncertain about allowable expenses.
Using an Accountant
Hiring a qualified accountant ensures your return is accurate and complete. Accountants can identify legitimate tax reliefs and ensure you don’t overpay. This is particularly useful if you have multiple income sources, claim a lot of expenses, or have foreign income.
The downside is cost—especially for last-minute assistance. During January, accountants are typically swamped with client requests. Booking early increases your chances of getting help when you need it most.
Using Online Tax Software
For a middle-ground approach, online tax software can guide you through the filing process. These tools offer a structured, question-based interface that makes it easier to complete your return. Many are HMRC-recognised and allow direct submission through the software.
These platforms are generally more affordable than hiring an accountant and less error-prone than doing everything manually, particularly for those with moderate tax knowledge.
Preparing for Filing: What You Need
Before you sit down to file, make sure you have all the required information ready. Having everything on hand can prevent delays and reduce the likelihood of errors.
Key Documents and Details:
- Your Unique Taxpayer Reference (UTR)
- National Insurance number
- Details of all income sources: employment, self-employment, property, dividends, interest
- Records of allowable expenses
- P60 or P45 if you’ve been employed
- Records of pension contributions
- Student loan repayment details if applicable
- Any payments on account already made
For self-employed individuals, accurate bookkeeping throughout the year helps reduce the stress of last-minute filing. If you’ve maintained detailed records of invoices, receipts, and business expenses, completing the return will be much smoother.
Timing Your Filing: Early vs. Last-Minute
Some people prefer to file their return months in advance. Others wait until the very last minute. While both approaches can technically meet the deadline, early filing comes with clear benefits:
- More time to correct errors
- Early awareness of your tax bill
- Easier access to accountant support
- Peace of mind and reduced stress
Filing at the last minute, while tempting, carries risks. High website traffic, login issues, missing documents, and unexpected technical problems can all lead to a missed deadline.
When Payment Is Due
Submitting your return is only part of the process. You must also pay any tax owed by the same 31 January deadline. This includes:
- The balancing payment for the tax year just ended
- The first payment on account for the next tax year (if applicable)
Payments must be made in full by midnight. However, the way you choose to pay affects whether the money reaches HMRC on time.
Why You Shouldn’t Wait Until the Final Hour
Even though you can technically file your return and make your payment right up to midnight, there are several good reasons not to do so:
- System overload: HMRC’s site often struggles with the volume of last-minute filers.
- Unforeseen issues: You could forget login details, run into identity verification problems, or experience internet connectivity issues.
- Payment failures: Your bank may have its own processing deadlines earlier in the day, meaning your payment might not go through on time.
Preparing well in advance gives you flexibility and reduces the chances of running into obstacles.
Steps to Take
To ensure a smooth and timely Self Assessment filing experience, consider the following steps:
- Register for Self Assessment and set up your HMRC online account early
- Maintain accurate financial records throughout the year
- Decide whether to use the HMRC portal, an accountant, or tax software
- Prepare all necessary documentation well before January
- File your return at least a few days ahead of the deadline
- Understand your payment method and its timeline
The Dual Deadline Explained
Most people are aware that 31 January is the deadline for filing their Self Assessment tax return. What some overlook is that the same date also applies to tax payments. This includes the balancing payment for the previous tax year, and in many cases, the first payment on account for the current tax year.
Failing to make your payment by midnight on 31 January results in automatic penalties and interest charges. Even if you filed your return on time, your account will be marked as late if the payment hasn’t been cleared.
Payment Processing Time Matters
Different payment methods have different processing times. A key mistake many taxpayers make is assuming that initiating a payment on 31 January automatically means HMRC will receive it that same day. In reality, it depends on how you pay.
Payments made through some methods clear instantly, while others take up to three working days. If your payment is received after the deadline—even by a few hours—it may trigger late payment interest and a 5% surcharge if left unpaid after 30 days.
Online Debit and Credit Card Payments
Paying directly through HMRC’s website using a debit card is one of the most popular methods. This is usually a same-day service, meaning the payment clears quickly and you receive immediate confirmation.
However, personal credit cards are no longer accepted. You can still use a business credit card, but additional fees may apply. Payments made using either method are processed the same day if completed before midnight.
It’s worth noting that the HMRC portal can become very busy on 31 January. Traffic overload can slow down payment confirmation and page responsiveness, so even though you may be within the deadline, you might run into technical delays.
Bank Transfers: BACS, CHAPS, and Faster Payments
Bank transfers are also a common way to pay HMRC, but not all transfers are created equal.
BACS Transfers
BACS payments are best avoided on the final day because they typically take three working days to clear. Initiating a BACS payment on 31 January means the money likely won’t reach HMRC until early February, making it late and subject to penalties.
CHAPS Transfers
CHAPS is a same-day service and is much better suited for last-minute payments. However, CHAPS transactions must be submitted before your bank’s daily cut-off time—usually between 2 pm and 4 pm. If you miss this window, the payment won’t be processed until the next working day.
Faster Payments
Faster Payments is a relatively quick method offered by most UK banks. These payments often clear within minutes but are not guaranteed to be instant. Some banks impose limits on transaction size or delay payments made outside business hours.
While Faster Payments can be suitable for near-deadline payments, it’s risky to rely on it too close to midnight due to potential delays in processing.
Paying via Direct Debit
Direct Debit is available through HMRC’s online system, but it must be set up well in advance. A new Direct Debit mandate can take up to five working days to process, while existing arrangements still require at least three days for payment clearance.
This method is ideal for spreading your tax payments across the year or for automated advance planning, but it’s not a solution for last-minute tax liabilities.
Telephone Payments
HMRC also accepts payments over the phone. You can call their payment line and use a debit or business credit card to make your payment. While this method generally works well, it comes with its own challenges.
Expect long hold times if you call on 31 January. The line will be extremely busy, and if you’re unable to get through in time, you risk missing the deadline. For this reason, it’s best to use phone payments only well before the final day.
Posting a Cheque
Paying your tax bill by cheque is another option, though increasingly less popular. Cheques must be received and cleared by HMRC before the deadline. This means posting several working days in advance. Given the potential for postal delays, it’s not a recommended method in January.
If you do choose to pay by cheque, ensure it’s accompanied by the correct payment slip and sent to the correct HMRC address.
Payment Confirmation and Record-Keeping
Whatever method you use, always retain proof of payment. If you pay online, take a screenshot of the confirmation screen and check your bank statement to verify the amount and date. For phone and postal payments, keep the receipt or postal certificate.
Having these records is vital if there’s ever a dispute with HMRC regarding the timing or receipt of payment. It provides evidence that you acted on time, even if technical or administrative delays occur.
What Happens If Your Payment Is Late
If HMRC does not receive your payment by midnight on 31 January, they will begin applying interest on the outstanding balance starting 1 February. In addition to interest, a 5% penalty will be applied if the tax remains unpaid after 30 days. Further penalties are added at six months and twelve months.
These additional costs can be significant. For large tax bills, a 5% surcharge adds hundreds of pounds in avoidable fees.
Setting Up a Budgeting Plan
To avoid the stress of a last-minute payment, consider setting up a budgeting plan months in advance. Estimate your tax liability and start setting aside funds regularly. Many taxpayers open a separate savings account dedicated solely to tax payments, transferring money into it monthly.
This strategy ensures you’re financially prepared when January arrives and eliminates the risk of not having enough funds available.
Payments on Account
If your tax bill is more than £1,000, HMRC usually requires you to make payments on account. These are advance payments toward your next tax bill and are split into two instalments: one due on 31 January and the second due on 31 July.
Each payment is typically 50% of your previous year’s tax bill. Not accounting for these in your budget can lead to a shortfall when the deadline arrives. Make sure to include both instalments in your financial planning.
Payment Plans and Time to Pay Arrangements
If you’re unable to pay your tax bill in full by the deadline, HMRC offers a Time to Pay arrangement. This allows you to spread your payments over a longer period through monthly installments.
You can apply online for this service if you owe less than £30,000 and have no other outstanding tax debts. Approval is usually quick, but you must apply before HMRC initiates debt recovery action. Interest will still apply, but late payment penalties can be avoided if the arrangement is agreed upon in advance.
Best Practices for Last-Minute Payers
If you do find yourself needing to pay on 31 January, follow these best practices:
- Use Faster Payments or CHAPS, depending on the time of day
- Avoid BACS and Direct Debit for same-day payments
- Complete the transaction well before 10 pm to avoid system crashes
- Take screenshots of payment confirmation pages
- Monitor your bank for any failed transactions
Immediate Consequences of Missing the Deadline
The most immediate consequence of a missed deadline is the automatic late filing penalty. HMRC applied a flat £100 fine for any return submitted after 11:59 pm on 31 January. This penalty applies whether or not you owe any tax and regardless of how late the return is.
The penalties escalate the longer your return or payment is delayed:
- Three months late: daily penalties of £10 for up to 90 days (maximum of £900)
- Six months late: an additional £300 or 5% of the tax due, whichever is higher
- Twelve months late: a further £300 or 5% of the tax due
In severe cases, penalties can be higher if HMRC believes the delay was deliberate or if you concealed income.
Interest on Late Payments
If your tax bill isn’t paid by the deadline, interest begins accruing from 1 February until the payment is made in full. The interest rate is set by HMRC and fluctuates depending on market conditions. This can substantially increase your tax bill, particularly if you are late by several months.
In addition to interest, HMRC also applies a 5% surcharge on any tax not paid by 30 days after the deadline. Additional 5% surcharges apply at the six-month and twelve-month marks.
Filing and Paying as Soon as Possible
Even if you’ve missed the deadline, filing your return and paying your tax as soon as possible can stop further penalties from building. Once your return is submitted, you’ll have clarity on how much is owed and can begin addressing the balance.
If you cannot pay the full amount right away, paying a portion is still beneficial. It reduces the interest charged and demonstrates to HMRC that you are trying to resolve the issue.
Can You Appeal a Penalty?
HMRC allows you to appeal late filing or payment penalties if you have a valid excuse. These are called “reasonable excuses,” and HMRC accepts them under certain circumstances.
What Qualifies as a Reasonable Excuse
- Serious illness or hospitalisation during the filing period
- Bereavement of a close family member
- Fire, flood, or theft affecting your records
- Technical issues with HMRC’s website
- Unexpected postal delays beyond your control
A reasonable excuse must cover the full period during which the deadline was missed. For example, being ill for one day does not justify being weeks late with no action taken in the meantime.
How to Appeal
You can submit your appeal online through your HMRC account or via a written letter. Be clear and provide as much evidence as possible—hospital records, death certificates, or email correspondence with HMRC can all support your claim.
Appeals should be submitted promptly. HMRC typically expects them within 30 days of the penalty notice.
Payment Plans for Overdue Tax
If you’re unable to pay your tax in full, HMRC may allow you to set up a Time to Pay arrangement. This is a structured payment plan that lets you pay off your tax bill in manageable monthly installments.
You can apply online if:
- You owe less than £30,000
- You’re within 60 days of the payment deadline
- You have no other active payment plans or tax debts
If you don’t meet these criteria, you’ll need to call HMRC directly to discuss your case. These plans are not guaranteed, but HMRC often agrees to them if you’ve filed your return and can demonstrate affordability.
Interest still applies on the outstanding amount, but entering into a payment plan can prevent further penalties.
Common Mistakes Leading to Late Filing
There are several recurring mistakes that contribute to missed deadlines. Being aware of these can help you stay ahead next year.
Waiting for a Paper Return
Many people mistakenly believe they’ll receive a paper tax return automatically. HMRC now expects most people to file online. If you wait for a paper form that never arrives, you may already be late.
Underestimating Time Requirements
Filing a tax return often takes longer than expected, especially if you haven’t kept good records. Trying to gather everything in the last few days of January rarely ends well.
Lost Login Credentials
If you forget your Government Gateway credentials and wait until the last minute to recover them, you may miss the deadline. Always check access to your HMRC account early in January or even December.
Banking Errors
Attempting to pay your tax on 31 January using a method like BACS, which takes days to process, will result in a late payment. Not all payment methods are equal, and timing is crucial.
Steps to Prevent Missing the Deadline Next Year
Avoiding the stress and cost of a missed deadline is easier than it seems. By planning ahead, you can ensure your return is submitted and your tax paid well before the deadline.
Keep Digital Records Year-Round
Use software or spreadsheets to track your income and expenses every month. Waiting until January to compile data increases the chance of errors and delays.
Set Calendar Reminders
Use your phone, computer, or physical calendar to set reminders for key dates:
- 5 October: register for Self Assessment if newly self-employed
- 31 October: paper return deadline
- 31 January: online return and payment deadline
- 31 July: second payment on account (if applicable)
File Early
You can file your tax return as soon as the tax year ends on 5 April. Many taxpayers mistakenly think they must wait until January, but filing early reduces stress and allows more time to plan for payment.
Budget for Tax Throughout the Year
Set aside a portion of your income each month into a dedicated savings account for tax. By January, you’ll have the full amount ready and won’t need to scramble for funds.
Seek Help Before It’s Too Late
If your tax situation is complex or you’re unsure about your return, speak to a professional well in advance of the deadline. Last-minute advice is harder to come by and more expensive.
Automate Where Possible
Set up reminders or automated calendar entries. You can even schedule your payment through your bank’s system if you know your liability in advance.
Monitoring for Penalty Notices
If you’ve missed the deadline, keep an eye out for correspondence from HMRC. Penalty notices are usually sent by post or made available in your online account. Ignoring these can escalate the situation quickly.
If you believe the penalty was applied in error, act swiftly. The earlier you engage with HMRC, the better your chances of resolving the issue without further cost.
Staying Calm Under Pressure
Missing the Self Assessment deadline is frustrating, but not the end of the world. The key is to stay calm, assess your situation, and act quickly. Filing your return and making partial or full payment right away is the most effective way to minimise the consequences.
In future years, avoid relying on the final hours of 31 January. Unexpected delays, errors, and tech issues become far less stressful when you’re not racing against the clock.
Digital Tools for Tax Efficiency
One of the most significant ways to simplify tax preparation is to integrate digital tools into your workflow. These tools help you log income and expenses throughout the year, reducing the risk of missing deductible items or filing inaccurate information.
Cloud-Based Accounting Software
Cloud accounting platforms allow real-time tracking of your finances. You can link your bank accounts, automatically categorise transactions, and generate tax-ready reports with just a few clicks.
They also provide audit trails, which can be helpful if HMRC ever queries your return. Plus, access is available across devices, meaning you can keep tabs on your financial health anytime.
Digital Receipt Storage
Keeping physical receipts is risky—paper fades, gets lost, or is misplaced. Use apps that let you scan, upload, and tag receipts in seconds. Many even integrate with your accounting software, streamlining expense tracking.
Understanding Your Allowable Expenses
Another area where taxpayers lose out is in the realm of allowable expenses. Not claiming legitimate deductions reduces your take-home income unnecessarily.
Common Deductible Costs
- Office equipment
- Internet and phone bills (proportion used for work)
- Business mileage and travel expenses
- Advertising and marketing
- Subscriptions to professional organisations
- Accounting fees
Ensure these expenses are properly documented and clearly tied to your business operations. If in doubt, refer to HMRC guidance or consult with a professional.
Building a Year-Round Tax Calendar
Filing your tax return and making payments are just two points in a broader financial cycle. Planning for them as part of an annual calendar can make the process more manageable.
Key Dates to Note
- 5 April: End of the tax year
- 6 April: New tax year begins
- 31 July: Second payment on account due
- October (varies): Paper return deadline
- 31 January: Online filing and payment deadline
Set up automatic reminders or calendar events for each milestone. This allows you to spread tasks across the year and avoid last-minute pressure.
Improving Record-Keeping Habits
Accurate record-keeping is essential for a smooth Self Assessment experience. It ensures your tax return is correct, substantiated, and submitted on time.
Tips for Better Records
- Maintain separate personal and business bank accounts
- Reconcile transactions monthly
- Store invoices, receipts, and correspondence
- Back up digital records in multiple locations
Good records are not just about meeting HMRC requirements—they also help you understand your business performance and plan for growth.
Leveraging Professional Support
While it’s possible to handle your own tax return, there are times when professional support is worth the cost. Accountants and tax advisers can help you navigate complex issues like:
- Capital gains
- Rental income from multiple properties
- Trading losses and carry-forward calculations
- VAT and Making Tax Digital compliance
You may also consider using a professional for a year to help set up your accounting systems, and then take over once you’re confident.
How to Respond to HMRC Enquiries
Occasionally, even if your return is accurate and timely, HMRC may raise a query or open an investigation. This can be random or triggered by inconsistencies or omissions.
Steps to Take
- Don’t panic—most enquiries are straightforward.
- Respond promptly and professionally.
- Provide requested documents and explanations.
- Keep communication in writing where possible.
If the matter is complex or you’re unsure how to respond, seek professional advice. Delays or poorly constructed responses can escalate the situation unnecessarily.
Preparing for the Next Tax Year
As soon as one tax year ends, preparation for the next begins. A few proactive steps in April can set the tone for better financial management throughout the year.
Review the Previous Year
Look at your submitted return and assess where the bottlenecks or issues occurred. Were records missing? Did you scramble for last-minute funds? Use this reflection to improve your process.
Set Financial Goals
Define how much you’d like to earn, save, and invest. Identify seasonal variations in income and expenses. This allows you to plan cash flow and set aside tax in proportion to your earnings.
Automate Regular Tasks
From tracking expenses to calculating mileage, many admin tasks can be automated using modern tools. The more you automate, the less chance you’ll fall behind.
Managing Tax When Your Income Changes
If you switch careers, go part-time, or take a break from work, your tax situation will likely change. Inform HMRC of major changes to your income or work structure, such as:
- Becoming employed again
- Ceasing self-employment
- Changing business structure (e.g. sole trader to limited company)
This helps avoid overpaying tax or missing out on deductions you’re eligible for.
Keeping Up with Tax Law Changes
Tax rules evolve. Staying informed about new legislation or upcoming changes to thresholds and deductions can make a significant difference.
Subscribe to official HMRC updates, follow credible tax blogs, or attend free webinars offered by business associations. Knowing what’s on the horizon helps you adjust your planning accordingly.
The Value of Financial Literacy
Understanding the basics of tax, business accounting, and financial management empowers you to make better decisions. Even if you outsource your taxes, having foundational knowledge ensures you’re in control.
You don’t need to be a finance expert—but grasping core concepts like gross vs net income, tax brackets, and deductible expenses gives you confidence and clarity.
Creating a Checklist for the Next Return
End each year by building a checklist of everything you need to submit your return. This list should include:
- UTR and login credentials
- P60 or P45 (if employed)
- Details of self-employed income
- Invoices and receipts
- Bank interest or investment income
- Rental income details (if applicable)
- Pension and gift aid contributions
Keep this checklist somewhere visible or in your accounting tool to ensure nothing is overlooked.
Conclusion
Navigating the Self Assessment process doesn’t need to be overwhelming, especially if you understand the critical deadlines, choose suitable filing and payment methods, and prepare throughout the year. This guide has covered everything from what happens if you file or pay at the last minute, to how payment processing times affect your liability, the consequences of missing deadlines, and the tools that can help make tax season far less stressful.
The central takeaway is that planning is essential. While you technically can submit your tax return up to midnight on 31 January, doing so carries risks. System slowdowns, banking delays, and last-minute errors can all result in penalties and interest charges. The same applies to tax payments — some methods process instantly, while others take days, potentially making an on-time payment appear late in HMRC’s eyes.
If you do miss the deadline, acting quickly is vital. File your return as soon as possible, pay what you can, and explore options such as Time to Pay arrangements or penalty appeals if you have a valid reason. Ignoring the issue only increases the financial and administrative burden.
Looking forward, there’s a lot you can do to improve your experience. From setting up a digital tax calendar and keeping better records to using accounting tools and understanding your allowable expenses, small steps taken early can eliminate stress later. Staying informed, budgeting throughout the year, and knowing when to seek professional help are key strategies to staying compliant and in control.
Whether you’re a sole trader, freelancer, landlord, or anyone with untaxed income, adopting a proactive, informed approach to tax will serve you better than leaving things until the last minute. With the right preparation, you won’t need to ask if your return or payment will be deposited at midnight, you’ll already be done well before then.