In today's digital market, customer-engagement (CE) on numerous platforms is vital for marketing success. This gives a reason to examine the structural relationship between CE, mental accounting, investor attitude, and loyalty for marketable financial products. This study uses a qualitative research design (ISM-Interpretive Structural Modeling) to emphasise structural links that can lead to investor loyalty. CE drives structural aspects. Mental accounting and investor attitude influence investor loyalty. This study solely analyses marketable financial products including mutual funds, SIPs, and certain insurance products. This study lacks empirical evidence. This study examined how mental accounting affects investor participation, sentiments, and loyalty. This knowledge will help design financial product marketing strategies because financial products have varying worth based on context, even though they have similar qualities. The study proposes a model on the structural relationship between CE, mental accounting, investors' attitude, and loyalty, which would disclose a new academic perspective along the strategic ramifications for the financial markets.