Sri Lanka Capital Gains Tax Calculator — 10% Flat Rate

Capital gains tax in Sri Lanka is a single, flat 10% on the gain you realise when you dispose of an investment asset. The rate is the same regardless of who you are (individual, company, or trust) and regardless of how long you held the asset. The statute that governs the regime is the Inland Revenue Act No. 24 of 2017 — the calculator above applies it line by line.

Step 1 — Determine the cost base (Section 37)

The cost base is what you spent acquiring and improving the asset. It combines three figures: the acquisition cost (or the 30-Sep-2017 market value if you elect the step-up), plus any capital improvements you made, plus the incidental costs you paid to acquire the asset (stamp duty on purchase, legal fees, notary fees, brokerage on the buy side). If you are unsure what stamp duty you originally paid on a property purchase, the Sri Lanka stamp duty calculator reconstructs it from the deed value so you can fold the correct figure into the cost base.

The 30-Sep-2017 step-up exists because the current CGT regime started on 1 April 2018. For any asset you acquired before 30 September 2017 — the day before the new law took effect — the First Schedule (paragraph 7) lets you substitute the market value at that date for the original cost. This ring-fences pre-regime appreciation, so you are taxed only on the gain since the law came in. The toggle on the calculator activates only when your acquisition date qualifies.

Step 2 — Determine the net consideration

The net consideration is the sale price agreed with the buyer lessany incidental disposal costs — broker commission, legal fees, notary charges, and similar selling expenses. The calculator subtracts these for you and labels the result "A" on the working.

Step 3 — Compute the gain

The gain is netConsideration − adjustedCostBase. If the result is negative, the calculator reports the capital loss but floors the taxable gain at zero — losses do not generate refunds. Under Section 36 of the IRA, losses can be carried forward against future investment-asset gains.

Step 4 — Apply exemptions (Third Schedule)

• CSE-listed shares: gains are exempt. A 0.30% Share Transaction Levy applies separately (deducted by your broker) and is not CGT.
• Principal place of residence: owned and occupied for at least 3 years, and no PPR exemption claimed in the previous 10 years.

If neither exemption applies, the calculator returns a tax line.

Step 5 — Apply the rate and compute net proceeds

The tax is taxableGain × 10% per Section 7(7) and the First Schedule, Part I. The net proceeds — the actual cash you walk away with — are saleConsideration − disposalCosts − tax. CGT is payable within one month of the realisation date using IRD Form IIT_CGT_001 (Asset Disposal Return).

Capital gains tax vs. income tax — which one applies?

Capital gains tax only applies to the realisation of an investment asset — something you held to appreciate in value, such as land you were not trading in. If buying and selling property or shares is your actual business, the profit is ordinary business income and is taxed under the normal income tax brackets instead, not at the flat 10% CGT rate. The same split applies to rent: collecting rent is income, not a capital gain. For the income side, use the Sri Lanka income tax calculator for salary and business profits, or the rental income tax calculator if you are taxed on rent received. CGT is charged once, on the gain at the point of sale; income tax recurs each year on what the asset earns.

Edge cases the calculator handles

• Same-day or very short holds. The 10% rate does not change with holding period — a one-week flip and a 20-year hold are taxed identically. Holding length only matters for the 3-year PPR test.
• Gains that net to exactly zero. When net consideration equals the cost base, the gain is zero and the tax line shows Rs 0 — no rounding artefact pushes it positive.
• Step-up that wipes out the gain. If the 30-Sep-2017 market value plus improvements exceeds the sale price, the result is a loss even on a nominally higher sale, because pre-2018 appreciation is excluded from the taxable base.
• PPR ticked but under 3 years. The calculator does not silently grant the exemption — it falls back to the 10% charge and shows a warning explaining why the holding does not qualify.

Records to keep before you file

The figure this calculator produces is only as defensible as the paperwork behind it. The IRD can ask you to substantiate every line of the cost base, so keep the original sale and purchase deeds, the notary's and broker's invoices, dated receipts and bank-transfer evidence for every capital improvement, and — if you used the 30-Sep-2017 step-up or inherited the asset — a registered valuer's report for the substituted value. For the principal place of residence exemption, hold on to utility bills, electoral registration, and bank statements showing the property as your address across the qualifying period. Retain these for at least five years after the realisation date. With the working in hand, complete IRD Form IIT_CGT_001 (Asset Disposal Return) and pay within one month of the sale; the "Copy working" button on the calculator gives you a plain-text version of the same line-by-line computation to attach to your records.

• Inland Revenue Act No. 24 of 2017 (with amendments) — Sections 7, 36, 37; First & Third Schedules
• IRD — Guideline on Gains from Realisation of Investment Assets
• Inland Revenue (Amendment) Act No. 45 of 2022 — retains 10% CGT rate
• Colombo Stock Exchange — Investor Education (CSE-listed share exemption)
• Inland Revenue Department of Sri Lanka — official site

The CGT rate, step-up date, and exemption conditions on this page were last cross-checked against the IRD's published act and guidelines on 2026-05-12. The page is reviewed every April (start of new SL Y/A) and whenever an Inland Revenue Amendment Act is gazetted. Non-resident withholding mechanics under Section 84 are out of scope for v1.