Sri Lanka Post Rate Calculator — Letter, Parcel, Registered & EMS

The calculator follows the published Sri Lanka Post Official Postal Tariff at slpost.gov.lk. Every rate band, surcharge and ceiling on this page is sourced from that schedule and cited in the breakdown table next to the rupee figure it produces. The legal basis for the schedule is the Sri Lanka Post Act No. 16 of 1995, which grants the Department of Posts the exclusive privilege of carrying letters and sets out the Minister's authority to gazette postage rates.

The calculation runs in five deterministic steps:

1. Resolve the rate tablefor the chosen combination of service class, scope (inland vs international), and — for international items — the destination zone. The zone groupings mirror the Universal Postal Union (UPU) country-zoning that Sri Lanka Post applies: Zone 1 (SAARC), Zone 2 (Asia & Pacific), Zone 3 (Europe & Middle East), Zone 4 (Americas, Africa & Oceania).
2. Look up the weight band. The calculator walks the resolved table in ascending order and picks the first band whose range covers the entered weight. If the item exceeds the maximum permitted weight for that service (2 kg for letters, 5 kg for printed papers, 20 kg for international parcels, 30 kg for inland parcels and EMS), you get a specific error and a suggestion to switch to a higher-weight service.
3. Add the registered-mail surcharge (Rs 100, flat) when Registered Post is selected and the service permits it. The registered surcharge is independent of weight; it pays for proof of posting and end-to-end tracking through the Sri Lanka Post network.
4. Add the AR (Acknowledgement of Receipt) card fee (Rs 75, flat) when AR is selected. AR is only permitted on items that already have a tracked delivery channel — Registered Post or EMS — because the post office needs a signature point at the destination to send the card back.
5. Add the insurance premium (Rs 20 per Rs 1,000 of declared value, or part thereof) when declared-value insurance is enabled, up to the maximum declared value of Rs 50,000. Insurance is only offered on Parcel Post and EMS, where Sri Lanka Post has the handling and tracking infrastructure to accept the liability.

The total is the sum of those lines, rounded to the nearest rupee. Sri Lanka Post itself publishes its tariff in whole rupees, so no fractional postage arises. To guard against off-by-one bugs around weight-band boundaries (501 g vs 500 g, 1001 g vs 1000 g), the data module ships two independent implementations of the calculation —calculateRateand calculateRateBySumOfParts — that share no helpers; both must agree to the rupee for the calculator to ship.

• Sri Lanka Post — Official Postal Tariff (slpost.gov.lk)
• Department of Posts (Sri Lanka Post) — homepage
• Sri Lanka Post Act No. 16 of 1995 (Parliament of Sri Lanka)
• Universal Postal Union — country zones & member registry

Rates and surcharges on this page were last cross-checked against the Sri Lanka Post Official Postal Tariff on 2026-05-16. If you find a discrepancy with a recently gazetted revision, please email [email protected] so the data module can be updated.