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Answers · Corporate income tax · YA 2026 · a financial year that ended in 2025

Year of assessment versus financial year end: which year am I filing?

The year of assessment (YA) is the calendar year after the one your financial year ended in: a year ending 31 Dec 2025, 30 Jun 2025 or any other day of 2025 is assessed in YA 2026. So the return due by 30 Nov 2026 is YA 2026, and the accounts behind it are the financial year that ended in 2025.

The two filings run on two clocks. The ECI is due 3 months after your year end; Form C-S is due 30 November of the year of assessment, whatever your year end.

Dates computed; first-year rules checked by hand Edition YA-2027 · sources verified through 24 Jul 2026

The rule: add one to the year your financial year ends in

Singapore assesses a company on the profit of the financial year that has already closed. The year in which that assessment falls is the year of assessment, and it is always the calendar year after the financial year end. The month does not matter: 31 Dec 2025, 30 Jun 2025 and 31 Mar 2025 are all YA 2026.

The financial year whose profit a YA taxes is that YA's basis period. For every year except a long first one, the basis period and the financial year are the same window, so the two words name one thing.

The confusion comes from the label. Your accounts say "financial year 2025"; the ECI, the Form C-S and the notice of assessment all say "YA 2026". They are the same year, seen from the two ends of it.

Your year end, its YA, and both due dates

The table below is the engine's own filing plan for a twelve-month year ending on each of the last twelve month ends. The YA is the year after the year end; the ECI date is the last day of the third month after it; the Form C-S date is 30 November of the YA.

The twelve most recent month ends, with the year each one is assessed in
Financial year endedYear of assessmentECI due byForm C-S due by
30 Sep 2025YA 202631 Dec 202530 Nov 2026
31 Oct 2025YA 202631 Jan 202630 Nov 2026
30 Nov 2025YA 202628 Feb 202630 Nov 2026
31 Dec 2025YA 202631 Mar 202630 Nov 2026
31 Jan 2026YA 202730 Apr 202630 Nov 2027
28 Feb 2026YA 202731 May 202630 Nov 2027
31 Mar 2026YA 202730 Jun 202630 Nov 2027
30 Apr 2026YA 202731 Jul 202630 Nov 2027
31 May 2026YA 202731 Aug 202630 Nov 2027
30 Jun 2026YA 202730 Sep 202630 Nov 2027
31 Jul 2026YA 202731 Oct 202630 Nov 2027
31 Aug 2026YA 202730 Nov 202630 Nov 2027

Read the two right-hand columns together and the shape of the year appears. For a December year end the ECI falls on 31 Mar 2026 and the return on 30 Nov 2026, eight months apart. For a June year end the ECI falls on 30 Sep 2025, in the same calendar year as the year end, and the return not until 30 Nov 2026, fourteen months later. Any year end from January to September has its ECI in before its YA has even begun; only an October, November or December year end sees the ECI fall inside the YA.

A year that ends mid-month is outside IRAS's month-end table and takes the plain reading for the ECI: the same day of the month 3 months on. See the ECI page, with the waiver.

A new company: which YA is the first one

A company's first year of assessment is the one whose basis period contains its incorporation date, and a YA's basis period should not run past twelve months. Those two rules decide the first year. The first YA is not simply the calendar year the company was incorporated in: the company worked below was incorporated in 2024 and its first YA is 2025. If the first accounting period, incorporation to the first year end, is twelve months or less, it is one basis period and one YA: the year after the year end, like any other year. If it is longer than twelve months, IRAS assesses it as two YAs: the opening months from incorporation are the earlier YA, and the exact twelve months ending on the year end are the later one.

Worked, on IRAS's own example

Incorporated 15 Apr 2024, first year end 30 Jun 2025: 442 days, two YAs

This is the company in IRAS's explanatory notes to the YA 2026 Form C-S. The engine cuts its first period at twelve months before the year end, 30 Jun 2024, and the basis periods it derives are the ones the notes give.

A company incorporated 15 Apr 2024 with a first year end of 30 Jun 2025
LegBasis periodDaysYear of assessment
Opening stubFrom incorporation to the day before the last twelve months15 Apr 2024 to 30 Jun 202477YA 2025
The last twelve monthsEnding on the first year end1 Jul 2024 to 30 Jun 2025365YA 2026
Second financial year1 Jul 2025 to 30 Jun 2026365YA 2027

One return and one ECI, not two of each. The filing plan the engine derives for this company is a single ECI due by 30 Sep 2025, 3 months after the first year end, and a single Form C-S for YA 2026 due by 30 Nov 2026. The YA 2025 figures go inside that YA 2026 return; the form takes both years and there is nothing separate to file for YA 2025.

Worked, the short shape

Incorporated 15 Mar 2026, first year end 31 Dec 2026: 292 days, one YA

Under twelve months, so no split. The engine derives one basis period, 15 Mar 2026 to 31 Dec 2026, assessed in YA 2027: ECI due by 31 Mar 2027, Form C-S due by 30 Nov 2027. A first year end within twelve months of incorporation is the simple way to keep the first year to one YA.

How the profit is divided between the two YAs

IRAS attributes the income and expenses of a split first period to the two basis periods directly where they can be identified, and allows apportionment by days where they cannot. Simpler Tax does the first: each leg's pack is computed from the entries dated inside that leg's window, the same way any other year's is. It does not apportion a figure by day count. If part of your first-period profit cannot be placed in one leg by its date, that division is yours to make before the figures go on the return.

The start-up exemption counts from the first YA

The start-up tax exemption, for a company that qualifies, runs over its first three consecutive years of assessment, and the first is the YA of the basis period it was incorporated in. For the worked company that is YA 2025, a basis period of 77 days, and it uses up the first of the three exemption years however little profit it holds. The split does not move the count; it only shows where it starts. See the start-up exemption, worked.

What this page does not compute

A first period so long that even its opening months run past twelve months is an attribution across more than two YAs. A company can only have one with the Registrar's approval, since without it the first year end is at most 18 months after incorporation. Simpler Tax does not work that shape out. Its basis view leaves the whole period under the later YA, YA 2027 for a company incorporated 1 Jan 2024 with a first year end of 31 Mar 2026, while the note on its year map still describes the ordinary two-YA split. The two do not agree, and this page has no table for it: with a period that long, take the attribution from your accountant.

The cut itself is made on a day count, not on the calendar: a first period of 366 days is one basis period, 367 days is two. In a leap span that puts the boundary one day either side of where "twelve months" falls, which matters only if your first year end is within a day of the anniversary.

The first return IRAS asks for

IRAS expects a new company's first return two years after the year of incorporation: a company incorporated in 2024 is first asked for YA 2026, which is what the split above produces, and what a first year of twelve months or less that closes in the year after incorporation produces too. The default is wrong only for a company whose first accounts closed in the year it was incorporated. If that is you, and the company traded or received income in that year, the YA after incorporation is a real YA with a return of its own, and IRAS's filing FAQ says to request that return through the "Request for Income Tax Return for Newly Incorporated Companies" e-service rather than wait to be asked.

The ECI does not wait either: it is due within 3 months after the first financial year end, as after every other, unless both waiver conditions hold for that year. See every first-year filing and its date.

Do it in Simpler Tax

The year map names your YA, and both dates, from two fields

Settings takes the incorporation date and the first financial year end, and the engine derives every financial year from them: the YA each one belongs to, its ECI date and its 30 November date, on the desk's year map. A first period longer than twelve months shows on the Tax screen as its two YAs, each with its own pack, under the one return the later YA files. Simpler Tax files nothing; it tells you which year you are filing and what goes in it.

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Questions people ask

My financial year ends on 31 March 2025. Which year of assessment is that?

YA 2026. The year of assessment is the calendar year after the one the financial year ended in, whatever month it ended. Its ECI was due by 30 Jun 2025 and its Form C-S is due by 30 Nov 2026.

Is YA 2026 the same thing as the 2026 financial year?

No. YA 2026 assesses the financial year that ended in 2025. The 2026 financial year, whenever it ends, belongs to YA 2027 and is filed by 30 Nov 2027 at the latest.

What is a basis period?

The period whose profit a year of assessment taxes. For every year but a long first one it is simply the financial year in your accounts. A first accounting period longer than twelve months is two basis periods: the opening months, and the twelve months ending on the year end.

My first financial year is longer than 12 months. How many returns do I file?

One. The period is assessed as two years of assessment, but both go in the single return for the later one, due 30 November of that year. There is no separate return for the earlier YA. The ECI is one filing too, due 3 months after the first year end.

When is a new company's first ECI due?

Within 3 months of its first financial year end, unless both waiver conditions hold for that year: revenue of S$5,000,000 or below and a nil ECI. A company incorporated 15 Apr 2024 with a first year end of 30 Jun 2025 has its first ECI due by 30 Sep 2025.

Can I choose a year end that avoids the two-YA split?

Yes: keep the first financial year end within twelve months of incorporation. A first period of twelve months or less is one basis period and one year of assessment. Simpler Tax's setup offers first year ends within 18 months of incorporation, the limit its engine holds for a first year without the Registrar's approval, and asks you to confirm that approval before it accepts a later one.

Which year of assessment does the start-up tax exemption count from?

From the company's first year of assessment, which is the one its incorporation date falls in. For a split first year that is the opening stub, however short: the exemption runs for three consecutive years of assessment from there, so a stub of 77 days uses up the first of them.

Sources

Statutory figures on this page are read from the Simpler Tax rulebook at build time, edition YA-2027, every source last checked 24 Jul 2026. The rulebook entries named below are the ones this page was computed from; the IRAS pages are what they were verified against.