Quarterly Income Tax Instalment Calculator for Y/A 2026/27
Enter last year's tax and the withholding you expect. Get each quarterly instalment under the Act No. 11 of 2026 rules, with due dates, so you can budget and avoid late payment interest and penalties.
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Why plan instalments? Late payment of any instalment carries interest of 1.5% per month or part month from the due date, plus a 10% penalty if it is still unpaid 14 days later. Due dates: Q1 Aug 15 · Q2 Nov 15 · Q3 Feb 15 · Q4 May 15. Pay the correct amount through RAMIS.
From Y/A 2026/27 no Statement of Estimated Tax (SET) is filed. For Y/A 2025/26 the old SET basis still applies: choose it in the calculator, or use the SET calculator.
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Quarterly income tax instalment FAQs
What instalments are, the due dates, how each one is worked out from 2026/27, and what happens if one is missed.
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They are payments of income tax during the year, under section 90 of the Inland Revenue Act, instead of one payment after the year ends. Companies, partnerships and individuals with business, rental or other income not fully covered by withholding pay them. They are not Advance Income Tax (AIT): in the Act, AIT is tax withheld at source from interest, rent, dividends and similar payments, and AIT withheld from you counts as a credit against your instalments.
Quarterly income tax instalments are due on 15 August, 15 November, 15 February and 15 May (section 90(2) of the Inland Revenue Act). Interest of 1.5% per month or part month runs on any unpaid amount from the due date, and an instalment still unpaid 14 days after its due date also attracts a 10% penalty.
Each instalment is (A minus C) divided by B. A is the tax payable on last year's taxable income, C is the instalments already paid plus tax withheld or to be withheld during the year (APIT, WHT and AIT), and B is the number of instalments left, including the current one. You may use an estimate of this year's tax as A only if last year had no taxable income or you expect lower income this year, following IRD Circular SEC/2026/E/06.
The standard company rate is 30%. A 15% rate applies to qualifying export service income and foreign source income received in foreign currency and remitted through a bank, and 45% applies to betting and gaming, liquor and tobacco. From Y/A 2026/27, instalments start from the previous year's tax, not an estimate of this year's. Check current IRD guidance.
Yes. For years of assessment before 1 April 2026, A is the estimated tax in your Statement of Estimated Tax under sections 91 and 92, and C counts only tax paid or withheld before each due date. Act No. 11 of 2026 removed the SET from Y/A 2026/27, so no SET is filed for 2026/27 or later years.
Interest of 1.5% per month or part month is charged on the unpaid amount from the due date until payment. If the instalment is still unpaid 14 days after the due date, a penalty of 10% of the unpaid amount is added. Catching up at the next quarter does not cancel a penalty that has already been charged.
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