A folio number is a unique number assigned by the mutual fund corporation to each mutual fund investor.
The mutual fund company assigns a folio number to an investor as they make their first investment in a fund.
If you invest in two funds from the same AMC, your folio numbers can be same to both.
The amount of folios that an investor may have is unrestricted.
As a result, an increase in the number of folios does not always imply a rise in the number of investors.