Sri Lanka Provisional Tax Ait

Sri Lanka provisional tax via Advance Income Tax (AIT) quarterly instalments under s 90 of the Inland Revenue Act — who pays, calculation, due dates and penalties.

Sri Lanka · tax year 2025 · changed 25 Jun 2026

Approved by Lal kumarasiri · 3 Nov 2026

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Key figures: Sri Lanka, 2025

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Companies (all CIT payers)

All resident companies with a CIT liability are required to pay quarterly AIT instalments under s 90 of the IRA. Also applies to non-resident companies with a Sri Lanka tax liability.IRA s 90

Individuals with business income

Self-employed individuals and individuals with business income (not fully covered by APIT withholding) must make quarterly instalment payments.IRA s 90; IRD AIT Individual Guidance

Basis of calculation

Instalments are calculated based on: (a) the prior year's assessed tax liability (most common method), OR (b) an estimate of the current year's income tax liability. Companies may choose whichever is appropriate.IRA s 90

Exclusions from AIT base

Gains from realisation of investment assets (capital gains) are excluded from the AIT instalment calculation base.IRA s 90

Q1 instalment

Due by 15 July (for Y/A 1 April–31 March)IRA s 90; IRD AIT Payment Schedule

Q2 instalment

Due by 15 OctoberIRA s 90; IRD AIT Payment Schedule

Q3 instalment

Due by 15 JanuaryIRA s 90; IRD AIT Payment Schedule

Q4 instalment (balance)

Due by 15 April (after year-end). Final balance of tax (after deducting all AIT instalments and WHT credits) due with the annual return by 30 November.IRA s 90; IRD AIT Payment Schedule

The full skill

Sri Lanka Provisional Tax / Advance Income Tax (AIT)

Companies (all CIT payers) — All resident companies with a CIT liability are required to pay quarterly AIT instalments under s 90 of the IRA. Also applies to non-resident companies with a Sri Lanka tax liability. (IRA s 90)
Individuals with business income — Self-employed individuals and individuals with business income (not fully covered by APIT withholding) must make quarterly instalment payments. (IRA s 90; IRD AIT Individual Guidance)
Basis of calculation — Instalments are calculated based on: (a) the prior year's assessed tax liability (most common method), OR (b) an estimate of the current year's income tax liability. Companies may choose whichever is appropriate. (IRA s 90)
Exclusions from AIT base — Gains from realisation of investment assets (capital gains) are excluded from the AIT instalment calculation base. (IRA s 90)
Q1 instalment — Due by 15 July (for Y/A 1 April–31 March) (IRA s 90; IRD AIT Payment Schedule)
Q2 instalment — Due by 15 October (IRA s 90; IRD AIT Payment Schedule)
Q3 instalment — Due by 15 January (IRA s 90; IRD AIT Payment Schedule)
Q4 instalment (balance) — Due by 15 April (after year-end). Final balance of tax (after deducting all AIT instalments and WHT credits) due with the annual return by 30 November. (IRA s 90; IRD AIT Payment Schedule)
Penalty for underpaid instalments — 10% penalty on the underpaid or unpaid AIT instalment amount. percent (IRA s 90; IRD AIT Penalty Notice)
Credit against final tax — AIT instalments paid are credited against the final CIT liability assessed at year-end. Excess AIT (overpayment) may be refunded or carried forward. (IRA s 90; IRD Return Processing Guidance)
WHT credit — Withholding taxes deducted from income received (e.g. AIT on dividends, interest) are also credited against the final CIT/personal income tax liability. (IRA s 90B; First Schedule; IRD AIT/WHT Credit Guidance)
Payment method — Via RAMIS (IRD online portal) or through authorised banking channels. (IRD RAMIS – www.ird.gov.lk)

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Approval history

Past review records describe the work recorded at the time. The approval shown at the top of this skill applies to the current text.

Lal kumarasiri
25 Jun 2026 · LK
Historical outcome: approved · Record status: current

Issue history

No issues recorded.

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Sri Lanka Provisional Tax / Advance Income Tax (AIT)

Companies (all CIT payers) — All resident companies with a CIT liability are required to pay quarterly AIT instalments under s 90 of the IRA. Also applies to non-resident companies with a Sri Lanka tax liability. (IRA s 90)

Individuals with business income — Self-employed individuals and individuals with business income (not fully covered by APIT withholding) must make quarterly instalment payments. (IRA s 90; IRD AIT Individual Guidance)

Basis of calculation — Instalments are calculated based on: (a) the prior year's assessed tax liability (most common method), OR (b) an estimate of the current year's income tax liability. Companies may choose whichever is appropriate. (IRA s 90)

Exclusions from AIT base — Gains from realisation of investment assets (capital gains) are excluded from the AIT instalment calculation base. (IRA s 90)

Q1 instalment — Due by 15 July (for Y/A 1 April–31 March) (IRA s 90; IRD AIT Payment Schedule)

Q2 instalment — Due by 15 October (IRA s 90; IRD AIT Payment Schedule)

Q3 instalment — Due by 15 January (IRA s 90; IRD AIT Payment Schedule)

Q4 instalment (balance) — Due by 15 April (after year-end). Final balance of tax (after deducting all AIT instalments and WHT credits) due with the annual return by 30 November. (IRA s 90; IRD AIT Payment Schedule)

Penalty for underpaid instalments — 10% penalty on the underpaid or unpaid AIT instalment amount. percent (IRA s 90; IRD AIT Penalty Notice)

Credit against final tax — AIT instalments paid are credited against the final CIT liability assessed at year-end. Excess AIT (overpayment) may be refunded or carried forward. (IRA s 90; IRD Return Processing Guidance)

WHT credit — Withholding taxes deducted from income received (e.g. AIT on dividends, interest) are also credited against the final CIT/personal income tax liability. (IRA s 90B; First Schedule; IRD AIT/WHT Credit Guidance)

Payment method — Via RAMIS (IRD online portal) or through authorised banking channels. (IRD RAMIS – www.ird.gov.lk)