SIP vs Mutual Fund (Lump Sum) Calculator

SIP vs lump sum — the honest answer

Most articles tell you "SIP is always better" because it sounds disciplined. The math tells a different story: in any rising market, the lump sum invested earlier wins, because more capital compounds for longer. Vanguard's well-known study found that lump sum beat dollar-cost averaging in roughly two-thirds of historical 10-year US periods.

When SIP genuinely wins

• You don't have a lump sum. SIP is how monthly income becomes investment.
• Markets are volatile or falling. SIP buys cheaper shares during dips.
• You're emotional. SIP removes timing decisions and reduces regret risk.
• You're new to investing. Behavioral consistency matters more than optimal math.

When lump sum wins

• You receive a windfall (bonus, inheritance, asset sale).
• Long horizon, strong fundamentals. Get the money working immediately.
• Tax-advantaged accounts. Use your annual IRA/ISA limit on day one of the year.
• Bear market with conviction. "Buy when there's blood in the streets."

A hybrid that beats both pure strategies

Many investors split: invest 50-70% as an immediate lump sum, then SIP the rest over 6-12 months. This captures most of the lump-sum mathematical edge while reducing the psychological pain of investing right before a 20% drawdown.

Worked example

Compare $60,000 invested as a lump sum vs $500/month over 10 years at 10% CAGR. Lump sum grows to about $155,600. SIP grows to about $102,500 on $60,000 invested. Lump sum wins by ~$53,000 — purely because the money was invested earlier.

Step-up SIP: the underrated winner

Increasing your SIP by 10% annually (matching salary growth) can grow your final corpus by 60-80% compared to a flat SIP. Most modern brokers and AMCs support step-up SIP at signup with no extra effort.