Sri Lanka Assessment Tax (Rates) Calculator

Assessment tax — most people call it rates— is the annual property tax a Municipal Council, Urban Council, or Pradeshiya Sabha charges on rateable property inside its area. Under section 230 of the Municipal Councils Ordinance (and the parallel powers in the Urban Councils Ordinance and the Pradeshiya Sabhas Act), the charge is a percentage of your property's annual value:

1. Annual rates = annual value × rate% ÷ 100. The annual value is the council valuer's estimate of the yearly rent the property could fetch; the rate percentage is fixed each year by your local authority's gazette. Because the rate differs by council — and often by main-road versus side-road band — this tool takes it as an input rather than hard-coding a national number.
2. Quarterly installment = annual rates ÷ 4. The rating year divides into four quarters (Jan–Mar, Apr–Jun, Jul–Sep, Oct–Dec) and you may settle the whole year at once or quarter by quarter.
3. Full-year rebate: pay the entire year's rates before 31 January and a 10% discount applies, so you pay annual rates × 0.90.
4. Quarterly rebate: pay a quarter before the end of its first month and that quarter gets 5% off. If all four quarters are paid on time, the year totals annual rates × 0.95 — a 5% saving.

The tool then compares three routes — no discount, the 10% full-year rebate, and the 5% quarterly rebate — and flags the cheapest. Because 10% beats 5%, paying the full year in January always wins when you can afford the lump sum; the quarterly route mainly eases cash flow. All arithmetic derives the four quarters and the annual totals from a single annual figure, so there is no rounding drift from adding quarters back up. Overdue rates are not computed here — they are recovered by warrant under the ordinance and the penalty varies by council, so the tool shows that as guidance only.

• Rating and Valuation Ordinance — annual value basis
• Colombo Municipal Council — Municipal Assessor's Department (assessment/rates)
• Seethawaka Purawara Urban Council — Assessment Tax (10% and 5% rebate mechanics)
• Buttala Pradeshiya Sabha — Assessment Tax explainer (example rate bands)

The payment mechanics on this page were last cross-checked against the cited council assessment pages and the Municipal Councils Ordinance §230 on 2026-07-15. The rate percentage is set per local authority by annual gazette — always confirm it against your own assessment notice.