Government Notifies Rules to Establish IST as India’s Common Time Reference

The Department of Consumer Affairs has notified the Legal Metrology (Indian Standard Time) Rules, 2026, paving the way for Indian Standard Time (IST) to become the common time reference for legal, administrative, commercial and other official purposes across the country, it was announced.

The rules were notified on August 27 and will come into force 180 days after their publication in the Official Gazette. The transition period is intended to give government departments, businesses, institutions and other organisations time to make the necessary changes to their systems and processes.

The move comes amid growing dependence on accurate and synchronised time across technology-driven systems. Banking and digital payments, telecommunications, railways, power networks, computer systems and government records increasingly rely on precise timestamps, making consistency in timekeeping critical for their smooth operation.

Under the new framework, the common IST reference is expected to improve the accuracy of timestamps for banking and digital payment transactions, support coordination across transport systems such as railways and airports, and strengthen the reliability of telecommunications and internet networks.

Accurate and synchronised time will also be important for power systems, government and legal records, as well as emergency and other time-sensitive services.

The framework is part of the government's broader ‘One Nation, One Time’ initiative aimed at establishing a secure and uniform time-distribution system across India.

The government is developing infrastructure to disseminate accurate Indian Standard Time through Indian institutions and Legal Metrology laboratories.

The rules also provide for the use of NavIC, India's satellite navigation system, along with other approved Indian timing sources for secure and reliable time dissemination.

At present, several systems rely on foreign satellite-based sources for timing. The development of an indigenous time-dissemination infrastructure is expected to provide an additional source for critical systems and reduce reliance on external timing infrastructure.

As part of the initiative, a White Rabbit Technology-based Indian Standard Time Dissemination Demonstration Network was commissioned at the Regional Reference Standard Laboratory in Bengaluru in July 2026.

The system has demonstrated the dissemination of IST for sectors including banking, telecommunications, power, transportation and digital governance.

The government has also demonstrated secure dissemination of Indian Standard Time between RRSL Bengaluru and NSE Chennai, in collaboration with CSIR-NPL, ISRO, SEBI, NSE, BSNL and other stakeholders.

The 180-day transition period will allow stakeholders to assess their existing systems, carry out technical modifications and prepare for compliance before the rules take effect.