Security deposits in India vary more by city than by property. The same two-bedroom flat commands ten months of rent up front in parts of Bengaluru and two in Mumbai. Neither number is written into law; both are convention, which means both are negotiable.
The rough map
Bengaluru has historically run the highest deposits in the country, though six months is now more common than ten in new lets. Chennai sits around three to six. Mumbai and Delhi NCR typically ask two to three. Hyderabad and Pune land between two and four. Kerala and Goa are usually two.
What is actually enforceable
The Model Tenancy Act of 2021 caps residential deposits at two months of rent — but it only applies in states that have adopted it, and adoption has been slow and partial. Check your state before assuming the cap protects you.
Red flags
A deposit demanded in cash with no receipt. A deposit paid to anyone other than the registered owner. A refund clause that lets the owner deduct for "normal wear". And any agreement that does not state, in rupees, what the deposit is and when it returns.
Getting it back
Photograph everything on the day you move in — every wall, every fitting, the meter readings. Email the photographs to the owner the same day so they are timestamped and acknowledged. This single habit resolves most deposit disputes before they start.