What is dollar cost averaging?
Dollar cost averaging (DCA) is an investment strategy where you invest a fixed amount of money at regular intervals, regardless of market conditions. Instead of trying to time the market with a large lump sum, you spread your investments over time.
How dollar cost averaging works
Example scenario
- Monthly investment: $500
- Investment period: 6 months
- Total invested: $3,000
- Fund: S&P 500 index
Monthly breakdown
- Month 1: $50/share — 10 shares
- Month 2: $45/share — 11.11 shares
- Month 3: $55/share — 9.09 shares
- Month 4: $40/share — 12.5 shares
- Month 5: $60/share — 8.33 shares
- Month 6: $48/share — 10.42 shares
The result
Total invested
$3,000
6 monthly contributions
Shares acquired
61.45
Across all six purchases
Average cost per share
$48.82
$3,000 divided by 61.45 shares
Average market price
$49.67
Sum of prices divided by 6 months
Your average cost came in below the average market price over the period. That is the arithmetic behind DCA: fixed dollar amounts buy proportionally more shares when prices fall.
Benefits of dollar cost averaging
Reduces market timing risk
Removes the need to predict market movements and reduces the risk of investing everything at a market peak.
Emotional discipline
Automates investing decisions, preventing emotional reactions to market volatility.
Lower average cost
Can reduce your average cost per share compared with a lump sum invested at the wrong time.
Budget-friendly
Lets you start investing with smaller amounts and build wealth gradually.
Simplicity
Easy to set up and maintain, requiring minimal investment knowledge or monitoring.
Volatility protection
Market downturns become opportunities to buy more shares at lower prices.
DCA vs lump sum investing
| Aspect | Dollar cost averaging | Lump sum |
|---|---|---|
| Risk level | Lower timing risk | Higher timing risk |
| Potential returns | Moderate, consistent | Higher if timed well |
| Emotional impact | Less stressful | More stressful |
| Capital required | Small amounts | Large amount upfront |
| Best for | Regular savers, beginners | Experienced investors |
How to implement DCA
Choose your investment amount
Decide how much you can afford to invest regularly. Start with an amount you're comfortable with, even if it's just $50 or $100 per month.
Select your investment frequency
Monthly is most common, but you can choose weekly, bi-weekly or quarterly. Monthly often aligns well with salary payments.
Choose your index fund
Select a broad market index fund such as an S&P 500 or total stock market fund. Look for low expense ratios and good tracking records — you can compare options in our index fund database.
Set up automatic investing
Most brokerages offer automatic investment plans. Set it up once and let it run. This removes emotion and ensures consistency.
Stay consistent
Continue your regular investments regardless of market conditions. The strategy works best when maintained long-term through various market cycles.
You can model different monthly contributions with the calculator to see how the schedule you pick compounds over your time horizon.