Short answer: there’s no single, always‑highest bank — advertised savings rates in Sri Lanka change often and depend on the specific product and balance tier. As of today (16 October 2025):

• Many large commercial banks advertise ordinary retail savings rates around ~2.0–3.5% p.a. (e.g., Commercial Bank’s Regular Savings ~2.0% p.a.). (combank.lk)
• Some specialist/affiliate savings products show higher rates (examples found today: Siyapatha/Sampath‑affiliated savings plans advertise up to about 5.0% for certain accounts/age groups; SDB’s corporate “Top Saver” tiers show higher rates for large balances (up to ~6%+ for very large corporate balances). (Siyapatha.lk)

What that means for you:

• If you want the absolute highest current advertised savings rate, you need to compare specific products (regular savings vs. promotional/online/children’s/senior/priority or corporate saver) and the balance tiers — the “highest” offer is usually a special product or a tier for larger balances, not a single universal retail savings account.
• Rates can change quickly; if you’d like, I can check live (bank websites and comparison pages) right now and return the current top 3 savings‑account offers in Sri Lanka (I’ll include the exact rate, balance requirement, product name and a link to the bank page).