Railway Board has approved the long-awaited merger of Chennai Mass Rapid Transit System (MRTS) with Chennai Metro Rail (CMRL), initiating integration of suburban corridor management under a single state-led framework and a two-year transfer of operations. The approval follows years of talks and is reflected in a draft memorandum of understanding outlining asset and responsibility transfers. The Railway Board issued an update on August 12, 2026 approving the draft MoU signed by Southern Railway and the Tamil Nadu government in May and setting a framework for a phased shift of operation and maintenance. The transition will proceed in two stages. Under the draft MoU Southern Railway will transfer MRTS assets and general operation and maintenance responsibilities within 90 days while excluding core train operations and maintenance. Over a two-year period train operations and remaining maintenance will be progressively transferred to CMRL, with the state to make the agreed payment in full or in instalments. Proposed assets for transfer include land, stations and other infrastructure covering 19 of the 21 MRTS stations, together with tracks, signalling and telecom systems, lifts and escalators, foot overbridges and EMU rolling stock. MRTS originated in the 1975 First Master Plan for Chennai and passenger services initially ran between Chennai Beach and Velachery; the corridor was extended to St Thomas Mount and commissioned in March 2026, including Puzhithivakkam and Adambakkam while one station remains not operational. The merger requires coordination at Chennai Beach and Fort, with platforms 9 and 10 at Beach proposed for MRTS services and a crossing arrangement at Fort to enable track connectivity. A single track between Fort and Beach is currently in place and any proposal to double that section will be reviewed by Southern Railway according to operational needs and land policy. A special committee of senior officials will oversee the merger, coordinated by the Convenor of the Chennai Unified Metropolitan Transport Authority; integration could improve maintenance and passenger facilities but may affect existing services and restoring direct trains from St Thomas Mount to Arakkonam and Gummidipoondi.