Dollar-Cost Averaging (DCA) Definition

Dollar-Cost Averaging is a strategy that allows an investor to buy the same dollar amount of an investment on regular intervals. The purchases occur regardless of the asset's price.

Dollar-cost averaging is a tool an investor can use to build savings and wealth over a long period. It is also a way for an investor to neutralize short-term volatility in the broader equity market. A perfect example of dollar cost averaging is its use in 401(k) plans.

In a 401(k) plan, an employee can select a pre-determined amount of their salary that they wish to invest in a menu of mutual or index funds. When an employee receives their pay, the amount the employee has chosen to contribute to the 401(k) is invested in their investment choices.

Dollar-cost averaging can also be used outside of 401(k) plans, such as mutual or index fund accounts. Additionally, many dividend reinvestment plans allow investors to dollar-cost average by making contributions regularly. 

Joe works at ABC Corp. and has a 401(k) plan. He receives a paycheck of $1,000 every two weeks. Joe decides to allocate 10% or $100 of his pay to his employer’s plan. He chooses to contribute 50% of his allocation to a Large Cap Mutual Fund and 50% to an S&P 500 Index Fund. Every two weeks 10%, or $100, of Joe’s pre-tax pay will buy $50 worth of each of these two funds regardless of the fund's price.

The table below shows half of Joe's $100 contributions to the S&P 500 index fund over 10 pay periods. Throughout ten paychecks, Joe invested a total of $500, or $50 per week. However, because the price of the fund increased and decreased over several weeks Joe’s average price came to $10.48. The average was higher than his initial purchase, but it was lower than the fund’s highest prices. This allowed Joe to take advantage of the fluctuations of the market as the index fund increased and decreased in value.