Short answer — the authoritative place is the Tamil Nadu RERA (TNRERA) website; major Indian property portals also show RERA‑registered (RERA‑approved) apartments for Chennai and let you filter/search by RERA number. Key sites:

• Tamil Nadu RERA (official) — the master list of all registered projects in Chennai; you can search by project name, promoter, district, or RERA registration number. (rera.tn.gov.in)

• MagicBricks — has a dedicated “RERA registered projects in Chennai” listing and project pages that show the RERA number/details. (MagicBricks.com)

• Housing.com — guides and pages that explain/check TNRERA registration and link to official records; many property listings show the RERA registration number. (Housing.com)

• 99acres, NoBroker, PropTiger, CommonFloor, IndiaProperty and similar portals — these sites display project pages that include the promoter’s RERA registration number or explicitly label projects as “RERA registered” (use each site’s filters/search). (Examples: these portals follow the same practice of showing RERA details for Chennai projects.) (MagicBricks.com)

How to use them (quick steps)

• For the definitive check: search the TNRERA site’s “Registered Projects” section and enter the project name, promoter, district (Chennai) or the RERA registration number. That gives official registration, approved plans and documents. (rera.tn.gov.in)
• On property portals: open the project listing and look for the RERA registration number / RERA badge on the project page; portals increasingly require displaying the number per TNRERA rules. If a listing lacks a RERA number, verify on the TNRERA site before proceeding. (MagicBricks.com)

If you want, I can:

• look up a specific project or locality in Chennai and confirm its TNRERA registration (I’ll search the TNRERA database and portal listings), or
• show step‑by‑step screenshots of how to find a project on the TNRERA site.

Which would you like me to do next?