T-bills (Treasury Bills), SDLs (State Development Loans) and Government bonds are all types of Government securities, but they differ in several key aspects, such as the issuing authority, maturity period, purpose, and level of risk. Here's a breakdown of the differences between them:


T-bills (Treasury Bills)

SDLs (State Development Loans)

Government Bonds

Issuing Authority

Government of India

State Government of India

Government of India


Short-term maturity periods, typically ranging from a few days to one year.

Medium to long-term maturity periods, ranging from a few years to a couple of decades.

Longer-term maturity periods, often ranging from several years to several decades.

Interest Payout

On Maturity

Every 6 months till maturity

Every 6 months till maturity

Bidding window

Mon - Tue, every week

Mon, every week

Tue - Thu, every week