Below is a practical, step‑by‑step guide to investing in Sri Lankan government securities (Treasury bills and Treasury bonds), plus key rules and where to get help.

What government securities are available

• Treasury bills (T‑bills): short‑term (standard 91, 182, 364 days) issued at a discount. (cbsl.gov.lk)
• Treasury bonds (T‑bonds): medium‑ to long‑term (typically 2–30 years), pay semi‑annual coupon. (cbsl.gov.lk)

Who issues and manages them

• The Central Bank of Sri Lanka (CBSL) issues/agents the securities and runs primary auctions; securities are held scripless in the Central Depository System (CDS). (cbsl.gov.lk)

Main routes to buy

1. Primary market (new issues / auctions)

   • Bids must be placed through a Primary Dealer (PD) or a licensed Commercial Bank that participates in government security auctions. Non‑dealer banks typically place bids via PDs. (cbsl.gov.lk)

2. Secondary market (buy/sell any time)

   • Buy or sell existing issues through PDs, licensed banks or brokers — tradable daily; prices and yields are market‑determined. (cbsl.gov.lk)

Step‑by‑step: how to invest (practical checklist)

1. Decide the instrument and tenor

   • Short term (liquidity / low duration) → T‑bills; longer income/interest → T‑bonds. Check current yields before deciding. (cbsl.gov.lk)

2. Choose a Primary Dealer or licensed bank/broker

   • Use a PD or bank that offers a retail platform or dealer service (many PDs offer online portals). Example PDs publish rates and user portals. (CAL.lk)

3. Complete KYC and open required accounts

   • You’ll need:
     • A rupee bank account for funds (for residents, a normal rupee account; non‑residents use an Inward Investment Account (IIA)). (cbsl.gov.lk)
     • A Securities Account in the CDS (the PD/bank will open this for you and hold the securities in scripless form). (cbsl.gov.lk)

4. Check minimum investments & fees

   • Minimum transaction amounts and fees vary by PD/bank (some retail minimums are shown on PD sites; e.g. some PD portals indicate Rs.500,000 minimums for online placements — confirm with your chosen dealer). (CAL.lk)

5. Place your order

   • Primary auction: place a competitive or non‑competitive bid via the PD/bank by the auction deadline.
   • Secondary: place buy/sell orders through your dealer or their trading platform. (cbsl.gov.lk)

6. Settlement and custody

   • If allotted, the securities will be recorded in your CDS account and interest/maturity proceeds credited to your nominated bank account. Settlement dates follow the CBSL auction/settlement calendar. (cbsl.gov.lk)

7. Receiving coupons and maturity proceeds

   • T‑bills: interest is realized at maturity (issued at a discount). T‑bonds: coupons paid semi‑annually; principal paid at maturity. (cbsl.gov.lk)

Important rules and practical notes

• Safety: government securities are considered sovereign (very low credit/default risk). (cbsl.gov.lk)
• Tax: CBSL notes government securities are generally given favourable treatment; confirm current tax rules with your bank or a tax advisor. (cbsl.gov.lk)
• Non‑resident investors: can invest using an “Inward Investment Account (IIA)” and non‑resident holdings are subject to aggregate caps (CBSL sets limits — check current cap levels before investing). (cbsl.gov.lk)
• Liquidity: there is an active secondary market via PDs and banks but liquidity and bid/offer spreads vary by issue and market conditions. (cbsl.gov.lk)

Where to get authoritative, up‑to‑date details

• Central Bank of Sri Lanka — Government Securities Market (auction calendar, PD list, FAQs, rules). This is the primary authority. (cbsl.gov.lk)
• Primary Dealers’ websites and your bank’s treasury/wealth desk — for current rates, platforms, minimums and to open accounts (examples: CAL, DFCC, HNB, etc.). (CAL.lk)

If you want, I can:

• Look up the current list of Primary Dealers and their contact details, or
• Fetch the next CBSL auction calendar and current indicative yields.

(If you want me to fetch live auction dates, current yields or a PD contact list now, I’ll pull those straight from the CBSL and PD sites.)