UK Tax Year 2026/27: Key Dates and Deadlines

When Does the UK Tax Year Start and End?

The UK tax year runs from 6 April to 5 April the following year. The current tax year, 2026/27, started on 6 April 2026 and ends on 5 April 2027. The previous tax year, 2025/26, ended on 5 April 2026.

So as of today, we are in the 2026/27 tax year. Any income you earn between 6 April 2026 and 5 April 2027 belongs to 2026/27 for tax purposes. Income earned before 6 April 2026 belongs to 2025/26, and that is the year you will report on the Self Assessment return due by 31 January 2027.

Here are the tax year dates side by side:

Tax year	Starts	Ends
2025/26	6 April 2025	5 April 2026
2026/27 (current)	6 April 2026	5 April 2027
2027/28	6 April 2027	5 April 2028

The tax year is sometimes called the fiscal year. It applies to Income Tax, National Insurance, Capital Gains Tax, ISA allowances, and most personal tax matters. It is different from the calendar year, and usually different from a limited company's accounting year, which can end on any date the company chooses.

If you ever lose track of where you are in the year, our financial week tool tells you the current tax week and how long is left until 5 April.

Why Does the UK Tax Year Start on 6 April?

The odd start date is a leftover from the 1700s. The English year used to begin on Lady Day, 25 March, which was also the traditional date for settling rents and debts.

In 1752 Britain switched from the Julian calendar to the Gregorian calendar and lost 11 days in the process. Rather than collect a full year's tax on a year that was 11 days short, the Treasury moved the start of the tax year from 25 March to 5 April. A further one day adjustment in 1800 shifted it to 6 April, where it has stayed ever since.

There have been proposals over the years to move the tax year to 31 March or 31 December to match other countries, but no change is planned. For now, 6 April to 5 April it is.

Key Self Assessment Deadlines for 2025/26 and 2026/27

If you are self-employed, a landlord, a company director with untaxed income, or you earn over certain thresholds, you file a Self Assessment return after each tax year ends. Right now the return that matters is for 2025/26, the year that ended on 5 April 2026.

Deadline	What is due
5 October 2026	Register for Self Assessment if 2025/26 is your first year
31 October 2026	Paper tax return for 2025/26
31 January 2027	Online tax return for 2025/26, plus any balancing payment
31 January 2027	First payment on account for 2026/27 (if applicable)
31 July 2027	Second payment on account for 2026/27
31 January 2028	Online return and balancing payment for 2026/27

A few points worth knowing:

Payments on account catch a lot of people out. If your tax bill is over £1,000 and less than 80% of your tax was collected at source, HMRC asks for two advance payments towards the next year's bill, each equal to half of the previous year's tax. The first lands on 31 January alongside your balancing payment, the second on 31 July. In your first year of Self Assessment this can feel like paying one and a half years of tax at once, so budget early.

Filing early does not mean paying early. You can file your 2025/26 return today and still wait until 31 January 2027 to pay. Filing in summer gives you months of notice on the exact bill, which makes saving for it far easier.

Late filing penalties escalate. Miss 31 January and you get an automatic £100 penalty even if you owe nothing. After three months, daily £10 penalties begin, up to £900, with further charges at six and twelve months. Interest runs on late payments too.

Deadlines for Limited Companies

Limited companies do not follow the 6 April to 5 April tax year. Each company has its own accounting period, usually twelve months ending on the anniversary of incorporation or a date the directors have chosen, such as 31 March.

The deadlines then run from the company's own year end:

Corporation tax payment: due 9 months and 1 day after the accounting period ends. A company with a 31 March 2026 year end pays by 1 January 2027.
Company tax return (CT600): due 12 months after the accounting period ends.
Annual accounts to Companies House: due 9 months after the company's year end (different rules apply to a company's first set of accounts).
Confirmation statement: due at least once a year, within 14 days of the end of your review period.

Note the order: the corporation tax payment is due before the tax return. Many companies file the return early so the payment figure is confirmed well ahead of the deadline.

Corporation tax rates for 2026/27 are unchanged. Companies with profits up to £50,000 pay the small profits rate of 19%. Profits above £250,000 are taxed at the 25% main rate, and profits between £50,001 and £250,000 get marginal relief, which produces an effective rate that climbs gradually between the two.

If you run your own company and pay yourself through a mix of salary and dividends, the timing of dividends around the 5 April year end matters more than ever this year (see the April 2026 changes below). Our guide to directors' remuneration covers how the salary and dividend mix works, and our accounting service handles year end accounts and CT600 filing as a package.

PAYE and Employer Deadlines

Employers work to a separate calendar of PAYE deadlines tied to the tax year. The key dates for 2026/27 are:

Deadline	What is due
On or before each payday	Report pay and deductions to HMRC under Real Time Information (RTI)
22nd of each month	Pay PAYE and NI to HMRC electronically (19th if paying by post)
31 May 2026	Give P60s to all employees on the payroll at 5 April 2026
6 July 2026	File P11D and P11D(b) for 2025/26 benefits in kind
22 July 2026	Pay Class 1A National Insurance on benefits (electronic)

For 2026/27, employees pay National Insurance at 8% on earnings between the primary threshold and the upper earnings limit, then 2% above that. Employers pay 15% on earnings above the secondary threshold of £5,000 a year (£96 a week), so employer NI now applies to almost every employee on the payroll.

To see what these rates mean for take-home pay, try our salary calculator.

VAT Deadlines

VAT deadlines do not follow the tax year either. They follow your VAT quarters, which depend on the stagger HMRC assigned when you registered.

For most VAT-registered businesses on quarterly returns, both the return and the payment are due one calendar month and 7 days after the end of each VAT quarter. A quarter ending 30 June 2026 means a return and payment due by 7 August 2026.

The VAT registration threshold for 2026/27 is £90,000 of taxable turnover in any rolling 12 month period. It is a rolling test, not a tax year test, so you need to check your trailing 12 months of turnover regularly rather than once a year. All VAT returns must be filed through Making Tax Digital compatible software.

If you are near the threshold or unsure which VAT scheme suits your business, our VAT advice service can help.

2026/27 Rates and Allowances at a Glance

Item	2026/27
Personal allowance	£12,570 (frozen until 2030/31)
Basic rate (20%)	Income up to £50,270
Higher rate (40%)	£50,271 to £125,140
Additional rate (45%)	Above £125,140
Dividend allowance	£500
Dividend tax rates	10.75% basic, 35.75% higher, 39.35% additional
Employee NI	8% main rate, 2% above upper limit
Employer NI	15% above £5,000 a year
Capital gains annual exempt amount	£3,000
Capital gains tax rates	18% basic rate, 24% higher rate
ISA allowance	£20,000
VAT registration threshold	£90,000
Corporation tax	19% to £50,000, 25% above £250,000, marginal relief between

Two things to watch in that table. First, the personal allowance starts to taper once your income passes £100,000, withdrawing £1 of allowance for every £2 of income above the limit. That creates a painful effective tax rate on income between £100,000 and £125,140, and it is one of the most common planning points we raise with clients.

Second, the frozen thresholds keep pulling more people into higher bands as wages rise, an effect known as fiscal drag. A pay rise that looks modest can tip you over £50,270 or £100,000 and change your tax position significantly.

What Changed in April 2026?

The start of the 2026/27 tax year brought two changes that affect a lot of small business owners.

Dividend tax went up. From April 2026, the basic rate of dividend tax rose from 8.75% to 10.75%, and the higher rate from 33.75% to 35.75%, both increased by 2 percentage points at the Autumn Budget 2025. The additional rate stayed at 39.35%. With the dividend allowance already down to £500, directors taking dividends will feel this directly. Run your own numbers with our dividend tax calculator.

Making Tax Digital for Income Tax went live. From April 2026, self-employed people and landlords with qualifying income over £50,000 must keep digital records and send quarterly updates to HMRC through compatible software, on top of a year end submission. The threshold drops to £30,000 from April 2027, so even if you are outside the rules this year, you may be inside them next year. If you are affected and not yet set up, sort your software now rather than scrambling before the first quarterly deadline.

UK Tax Year FAQs

What tax year are we in now?

As of June 2026, we are in the 2026/27 tax year, which started on 6 April 2026.

When does the 2026/27 tax year end?

The 2026/27 tax year ends on 5 April 2027. The 2027/28 tax year begins the next day, 6 April 2027.

Can I still file my 2025/26 tax return?

Yes. The 2025/26 tax year ended on 5 April 2026, and the online filing deadline is 31 January 2027. You can file any time before then, and filing early means you know your bill sooner without having to pay it sooner.

Why is the tax year different from the calendar year?

It is a historical quirk from the calendar change of 1752, when Britain lost 11 days switching to the Gregorian calendar. The old year started on 25 March, and the adjustments landed the tax year start on 6 April.

How IAK Can Help

Tax deadlines do not move, but they are easy to lose track of while you are running a business. Our North London team takes the calendar off your plate:

Self Assessment: we prepare and file your return early so you know your January bill months in advance
Limited company compliance: year end accounts, CT600, and Companies House filings handled together
Payroll and PAYE: RTI filed on time, every time, on a fixed monthly fee
MTD for Income Tax: software setup and quarterly submissions if the new rules apply to you

Whether you need personal tax support, full accounting services, or VAT advice, contact us and we will keep you ahead of every deadline in the 2026/27 tax year.