Credit Growth

Credit growth is how fast a bank's loan book (its "advances") expands, usually quoted year-on-year. Everything else on the spread engine measures profit per rupee lent — credit growth is about how many rupees there are to lend against.

Here's the point: earnings are margin × volume, and the rest of this map is almost entirely about margin. A bank can hold its NIM dead flat and still grow its interest income handsomely, purely by lending more. That's why every results call leads with "advances grew X%" — it's the growth story that a flat margin can't tell. The catch is that credit growth is the easiest number to flatter and the most dangerous to chase. The fastest way to grow a loan book is to lower your standards, and that bill arrives later.

Take the running ₹100 crore loan book earning a 4.55% spread, so NII of ₹4.55 cr.

Grow the book 15% to ₹115 cr, same spread:

• New NII = 4.55% × ₹115 cr = ₹5.23 cr — up ~15%, with no change in pricing at all.

That's the volume lever in one line: more rupees, same margin, more income. Now the risk. Suppose the growth came from a push into unsecured personal loans during a boom. The loans look fine for 12–18 months (everyone pays early on), so the book looks healthy and fast-growing. Then the cycle turns, and a slug of those loans slides down the classification ladder. The growth of 2024 becomes the NPAs of 2026. This lag is why regulators watch banks growing much faster than the system with real suspicion.

Credit growth lifts NII through volume rather than margin, and when it outruns deposit growth it drives the credit-deposit ratio up — a flag that the balance sheet is being stretched. Its dark twin is asset quality: loans booked fast in good times seed the next NPA cycle. The rate environment set by the repo rate shapes how much customers want to borrow in the first place.