8-4-3 Rule of SIP

The 8-4-3 Rule of SIP is a popular illustration of the power of compounding in equity mutual fund SIP investments — demonstrating how wealth accumulation accelerates dramatically in later years of a long-term SIP. The rule describes the following pattern assuming a 12% annual return: in the first 8 years of a SIP, the corpus doubles from the initial investment; it doubles again in just 4 more years (12 years total); and doubles yet again in only 3 more years (15 years total). The progressively shorter doubling time illustrates how compounding becomes exponentially more powerful as the invested corpus grows larger and generates increasingly large absolute returns. For example, a ₹10,000 monthly SIP at 12% grows to approximately ₹13.9 lakh in 8 years, doubles to ₹27.9 lakh by year 12, and doubles again to approximately ₹50 lakh by year 15. The 8-4-3 rule is widely used by Indian financial advisors, mutual fund distributors, and AMFI's investor education campaigns to motivate retail investors to remain committed to their SIPs through market cycles — emphasising that the most significant wealth creation occurs in the later years of the investment horizon, meaning investors who exit early (particularly during market downturns) miss the most powerful phase of the compounding curve.