January
Self-Assessment Tax Return Deadline
31 January is the deadline for the Self-Assessment Tax Return (SATR) each year. By this date, individuals within the Self-Assessment regime must ensure that their tax return is filed, any balancing payment for the previous tax year is paid, and (where applicable) their first payment on account for the next tax year is paid.
This deadline often catches people out because it brings together several obligations at once; the combined amount due can often be significant.
Leaving things until the final weeks of January can create unnecessary pressure, so it is always advisable to start preparing well in advance to avoid last-minute issues such as unexpected liabilities.
What actually falls due on 31 January?
- Your Self-Assessment Tax Return for the tax year ending the previous 5 April.
- Balancing payment — the final amount you owe for that tax year after accounting for PAYE, payments on account, etc.
- First payment on account for the current tax year (if your tax liability is high enough to trigger them).
For many people, especially the newly self-employed, landlords, or those with untaxed income, this is the moment they realise their tax bill is bigger than expected.
March
Planning for the tax year in April
March is a key planning month, as it is effectively the final opportunity to act before the tax year ends on 5 April. At this stage, individuals and businesses should review whether they have fully used any available allowances, exemptions, and reliefs before they are lost for the year.
Examples of allowances, exemptions and reliefs to consider utilising include:
- Maximising personal pension contributions,
- Making use of the capital gains tax annual exemption,
- Using the dividend allowance and considering ISA investments before the tax year ends.
Self-Assessment Tax Return penalties
Individuals that do not settle their Self-Assessment liabilities by the 31 January following the end of the tax year may be in line for penalties.
If tax remains unpaid 30 days after 31 January (i.e. the following 1 March), HMRC can charge a 5% late payment penalty on the outstanding amount.
The late penalty is in addition to the tax already due and any interest that continues to amount on the unpaid balance. Delaying payment can become expensive very quickly.
April
New tax year – 5 April
5 April marks the start of the new tax year for individuals, trusts and partnerships. This often also symbolises the introduction of new rules, regimes, thresholds, and changes to reporting obligations.
The new year brings opportunities to:
- Review remuneration strategies,
- Re-evaluate investment plans,
- Re-evaluate business structures to ensure strategies remain tax efficient.
ATED – the Annual Tax on Enveloped Dwellings
ATED is an annual tax regime that applies to companies owning UK residential property valued above £500,000.
For companies meeting the reporting obligations, a return must be submitted by 30 April each year, with payment due on the same date.
Businesses (particularly property holding companies) should review their position each year.
There are reliefs which prevent the need for an ATED charge to be paid. However, companies may still need to file an ATED return by 30 April in order to claim the relevant relief.
Why is an annual review essential?
Property values, usage, and ownership structures change. Each year, companies should reassess:
- Whether the property still falls within ATED
- Whether a relief applies
- Whether a revaluation is required
- Whether the company must file a return even if no tax is due
This is especially important for property investment companies, SPVs, and group structures where property use can shift.
May
Deadline for the submission of P60s
By 31 May, employers must provide a P60 to every employee who was on the payroll at 5 April. The P60 is an important year-end payroll document, as it summarises the employee’s total pay and tax deducted during the tax year.
- For employees, the P60 is often needed when completing tax returns, applying for mortgages, proving income, or dealing with other financial matters.
- For employers, issuing P60s on time is an essential part of year-end PAYE compliance and helps ensure employees have the correct records for their own tax affairs.
To stay ahead:
- Ensure payroll records for the year are fully reconciled by mid‑April
- Confirm employee details (names, addresses, NI numbers) are correct
- Issue P60s electronically where possible to streamline distribution
- Keep copies for your own records in case of employee queries
July
SATR – second POA deadline
For individuals within the Self-Assessment regime who are required to make payments on account, the second payment on account falls due on 31 July. This payment is the second advance instalment towards the current year’s tax bill.
It can often come as a surprise, particularly for taxpayers who are new to Self-Assessment or who have only recently become liable to payments on account. Forward planning is essential to avoid cash flow pressures and ensure funds are available when the deadline arrives.
By 6 July, employers must submit P11D forms. These report any taxable benefits provided to employees and directors in the tax year ended 5 April. This includes items such as company cars, private medical insurance, and other benefits in kind where reporting is required.
P11D is a significant compliance deadline; late filing can lead to penalties and may also affect the wider PAYE reporting process. Employers should ensure benefit records are accurate and complete well before the deadline, particularly where multiple benefits or complex remuneration packages are involved.
Why employers should prepare early
Benefits reporting can be complex, particularly where:
- Multiple benefit types exist
- Car and fuel benefits need precise calculations
- Directors receive mixed remuneration packages
- Records are held across different systems or departments
Starting early allows employers to:
- Reconcile benefit data
- Confirm which benefits were payrolled
- Identify missing information
Employment Related Securities (ERS)
6 July is the annual ERS return deadline. Employers must submit this return for any registered/unregistered share schemes, similar arrangements or issues of shares to employees/directors.
Even where there has been no reportable activity during the year, a nil return is often required.
The deadline can easily be missed particularly where schemes are dormant and where there is an assumption that no action is needed. Failure to file can trigger automatic penalties.
October
Self-Assessment Tax Return (SATR) registration
For individuals who are newly required to file under Self-Assessment, the deadline to register with HMRC is 5 October following the end of the relevant tax year.
Registering on time is important because it allows HMRC to issue the taxpayer’s Unique Taxpayer Reference (UTR), which is needed to complete and submit a tax return. Leaving registration too late can create delays and increases the risk of late filing penalties occurring.
December
Deadline for tax collection via PAYE code
Taxpayers who would prefer HMRC to collect any Self-Assessment tax due through their PAYE tax code (rather than through direct payment) must file their online tax return by 30 December.
Filing by 30 December will be a useful for individuals who want to spread the cost through payroll deductions, rather than paying the full amount in one go by 31 January. However, if the return is filed after 30 December, this option is lost and any outstanding tax must instead be paid directly to HMRC by the following 31 January.
Specific requirements must be met to be eligible for this option including:
- Less than £3,000 in tax owed,
- Sufficient PAYE income to collect the tax (with deductions not exceeding 50% of that income).
General recurring deadlines
Corporation Tax filing and payment deadline
For companies that are not within the quarterly instalment payment (QIPs) regime, there are two main corporation tax deadlines to keep in mind:
- The corporation tax payment deadline, which is 9 months and 1 day after the end of the accounting period,
- The filing deadline for the corporation tax return, which is due 12 months after the end of the accounting period.
Tax is payable before the return itself is due, meaning companies need to have sufficient financial information available in good time to calculate liabilities accurately and make payment on time.
Quarterly Instalment Payments (QIPs)
Companies that are considered ‘large’ or ‘very large’ for corporation tax purposes are generally required to pay their corporation tax through QIPs. Rather than paying tax after the year end, these companies must make payments in advance, usually across four instalments.
- Large companies
For a standard 12-month accounting period, the first two instalments are typically due in months 7 and 10 of the accounting period, with the remaining two instalments falling in months 1 and 4 after the year end.
- Very large companies
For a standard 12-month accounting period, ‘very large’ companies are required to pay their corporation tax earlier than ‘large’ companies. The instalments are typically due in months 3, 6, 9 and 12 of the accounting period.
The payment timetable is accelerated, so large companies need strong forecasting and regularly updated management accounts to ensure liabilities are calculated and funded in line with the required schedule.
VAT
In most cases, VAT returns must be submitted and any VAT due paid one calendar month and 7 days after the end of the VAT period.
Many businesses submit VAT returns quarterly, meaning they will face four separate filing and payment deadlines each year. As these obligations repeat regularly, businesses need robust systems and good record keeping, ensuring returns are completed accurately and on time.
Construction Industry Scheme (CIS)
Under the Construction Industry Scheme (CIS), contractors have monthly compliance obligations:
- A CIS return must be submitted to HMRC by the 19th of each month, covering payments made to subcontractors in the preceding tax month.
- Any CIS deductions must then be paid to HMRC by the 22nd of the month if payment is made electronically, or by the 19th if payment is made by post.
Given the recurring nature of these obligations, businesses operating within CIS should ensure that their records are accurate and kept up to date each month. Missing a filing or payment deadline can result in penalties, interest, and unnecessary compliance difficulties.
Making Tax Digital (MTD)
MTD is becoming an increasingly important area to monitor. From 6 April 2026, self-employed individuals and landlords with qualifying income over £50,000 will be required to submit quarterly updates to HMRC using compatible software.
The quarterly submission deadlines will be 7 August, 7 November, 7 February, and 7 May. Importantly, the tax payment deadline remains unchanged at 31 January, so while reporting will become more frequent, the timing of payment is not changing under these rules.
Taxpayers should also be aware that HMRC intends to reduce the income threshold in future years, meaning MTD obligations are expected to extend to more taxpayers over time.
Starting early makes a huge difference, we can help every step of the way
Preparing to meet your filing deadlines early gives you:
- Clarity – you know your tax bill months in advance.
- Time to save – spreading the cost is far easier than scrambling in January.
- Options -you can adjust payments on account, claim reliefs, or correct records without pressure.
- Peace of mind -no last‑minute panic, cashflow difficulties or risk of penalties.
Avoid unexpected tax bills
When you prepare early, you know your liability months in advance. That means:
- No cash‑flow shocks
- Time to budget or set aside funds
- Ability to adjust payments on account or claim reliefs
Most tax stress comes from people discovering their bill too late.
Avoid penalties and interest
Late filing or late payment penalties can be significant. Early preparation ensures:
- You meet every deadline comfortably
- You avoid interest charges
- You avoid HMRC chasing or compliance checks triggered by late submissions
Improve accuracy
Rushed returns lead to:
- Errors
- Omissions
- Incorrect claims
- Misreported income
Early preparation gives you time to check figures properly and ensure compliance.
Plan tax efficiently
Starting early gives you space to:
- Review reliefs and allowances
- Consider pension contributions
- Optimise dividends or salary
- Plan property or business decisions before the year ends
Good tax planning only works when you’re ahead of the curve.
Reduce stress
Preparing early means:
- No last‑minute rush
- No competing deadlines
- No pressure on you or your accountant
It turns tax compliance from a crisis into a routine.
Your business runs better
Early preparation supports:
- Better bookkeeping
- Stronger financial controls
- Predictable cash flow
- Fewer surprises for directors or shareholders
Good tax habits strengthen the whole finance function.
