Sri Lanka APIT Calculator — Monthly Employee Tax (2025/26)

The calculator implements the IRD's Table 01 (Monthly Tax on Regular Profits) for Year of Assessment 2025/26. The same monthly figure can be derived two equivalent ways, and this page runs both in parallel so you can see them match to the rupee:

1. Bracket walk (annual basis). Multiply your monthly gross by 12 to get annual gross. Subtract the personal relief of Rs 1,800,000 (Rs 150,000 a month) to get annual taxable income. Apply the progressive brackets in order, then divide by 12 to get the monthly APIT.
   • Rs 0 → Rs 1,000,000 : 6%
   • Rs 1,000,000 → Rs 1,500,000 : 18%
   • Rs 1,500,000 → Rs 2,000,000 : 24%
   • Rs 2,000,000 → Rs 2,500,000 : 30%
   • Above Rs 2,500,000 : 36%
2. Closed-form monthly formula (Table 01). The IRD publishes a per-bracket APIT = rate × M − constant formula so payroll software can short-circuit the bracket walk. The constants for Y/A 2025/26 are:
   • Rs 0 → Rs 150,000: rate 0%, constant Rs 0
   • Rs 150,000 → Rs 233,333: rate 6%, constant Rs 9,000
   • Rs 233,333 → Rs 275,000: rate 18%, constant Rs 37,000
   • Rs 275,000 → Rs 316,667: rate 24%, constant Rs 53,500
   • Rs 316,667 → Rs 358,333: rate 30%, constant Rs 72,500
   • Above Rs 358,333: rate 36%, constant Rs 94,000

The calculator runs both methods on every keystroke and surfaces a green “cross-check passed” line if they agree to the rupee. If you spot a divergence please email me — the brackets in this tool are kept in sync with the IRD's published tables, but new amendments do occasionally happen mid-year.

The optional “+ Bonus / lump-sum”mode implements the IRD's Table 02 procedure for a one-off payment. With the simplifying assumption that your monthly salary stays constant for the year and no earlier lump-sums have been paid YTD, the tax due on a lump-sum B is:

lumpSumTax = annualTax(monthlyGross × 12 + B) − annualTax(monthlyGross × 12)

For payslip-level accuracy when you have prior YTD figures, take the result here as a guide and reconcile against your employer's payroll system, which can use your actual month-by-month payment history.

• IRD — Tax Chart for Y/A 2025/26
• IRD — APIT Tax Table No. 01 (Monthly Tax Deductions from Regular Profits)
• IRD — APIT publications landing page (Tables 01, 02, 03)
• Inland Revenue Department of Sri Lanka — official site

Brackets, formulas, and worked-example values were last cross-checked against the IRD sources on 2026-05-16. The personal relief was raised from Rs 1,200,000 to Rs 1,800,000, and the 12% slab was removed, effective 1 April 2025 under the Inland Revenue (Amendment) Act No. 2 of 2025.