 Self-financing portfolio

A portfolio is self-financing when every change in its asset holdings is paid for entirely by selling or buying assets within the portfolio, with no external cash added or removed.

A **self-financing portfolio** is a concept in finance and investment that refers to a portfolio of assets in which any changes in the portfolio's composition are financed entirely through the portfolio's own changes in value, rather than through external cash flows (such as additional investments or withdrawals). In other words, a self-financing portfolio does not require any external funding to maintain or adjust its positions.