How much money does GiveIndia earn from the interest of accumulated payroll giving accounts?

This amount is much less than most donors think it will be. Read on

Assuming a user donates Rs100 per month and the bank provides standard 3.5% on "quarterly minimum balance", the total interest we earn on a person who has an account balance of Rs1,200 is Rs19, or 1.6% p.a. effectively.

On an overall outstanding balance of, say, Rs1 crore, that comes to Rs1.6 lacs in interest. Given that a large amount of donors don't accumulate money for that long, roughly 60+% of PRG contributions by value are donated regularly. Thus, as against roughly Rs9-10 lacs in fees that we would have billed per crore deducted, only Rs40 lacs would have earned interest @ 1.6%, i.e., we would earn Rs64,000 p.a. in interest per crore deducted.

Thus, Net Effective Interest Earned on Payroll Giving donations is roughly 0.64% p.a., or Rs64,000 per Rs1 crore.