Dollar Cost Averaging
Invest a fixed amount on a fixed schedule to lower your average cost, dodge timing stress, and stay consistent.
TL;DR
- Invest a fixed dollar amount on a fixed schedule, no matter what the market is doing.
- The same cash buys more shares when prices fall and fewer when they rise, lowering your
averageCost. - Automating it removes timing stress and keeps you investing through the scary months.
How DCA Works
Fixed Amount, Fixed ScheduleInvest the same dollars on the same day, every time.
$500 on the 1st, every monthMore Shares When CheapThe same cash buys more shares when the price is low.
$500 at $25 = 20 sharesFewer Shares When PriceyAnd it buys fewer shares when the price is high.
$500 at $50 = 10 sharesLower Average CostYour cost per share lands below the average price.
Total spent / total shares boughtDCA vs Lump Sum
Lump Sum Usually WinsMarkets rise most years, so investing all at once often comes out ahead.
Lump sum wins about 2 of 3 timesDCA Cushions a CrashSpreading in protects you if prices drop right after.
Uninvested cash dodges the dipDeploy a Windfall SlowlySplit a big amount across three to six months.
$60k -> $10k/mo for 6 monthsPeace of Mind CountsThe best plan is the one you will actually stick to.
Less regret = you stay investedAutomate It
401(k) PayrollEvery paycheck deduction is dollar cost averaging by default.
15% of pay, auto-investedBank Auto-TransfersSchedule a transfer into your fund each payday.
Auto-buy on payday, no thinkingReinvest DividendsDRIP keeps the buying going with your payouts.
Payouts auto-buy more sharesWatch Small FeesOld brokers may charge per trade; use free buys.
Commission-free funds onlyThe Behavioral Payoff
Removes the GuessworkNo agonizing over the perfect day to buy.
The schedule decides for youTurns Dips Into SalesA crash becomes a discount instead of a scare.
Lower prices = more sharesBeats the SidelinesCash waiting to buy the dip usually just misses out.
Invested beats waitingKeeps You ConsistentSmall automatic buys build a habit that lasts.
Consistency beats timingTips
- Line up your
autoInvestdate with payday so the money is invested before you can spend it, turning every paycheck into a buy. - For a large windfall, spread it over three to six months of
DCAto balance the math against the fear of buying right before a drop.
Warnings
- Do not pause your
DCAwhen the news turns grim; downturns are exactly when your fixed amount buys the most shares. - Watch for per-trade commissions at older brokers; frequent small
recurringbuys can rack up fees, so use commission-free funds.
In Practice
See how fixed $500 buys lower your average cost below the average price when the market swings.
You invest $500 a month into an index fund over four months while the price bounces around.
- Month 1: price $50 -> $500 buys 10.0 shares.
- Month 2: price $40 -> $500 buys 12.5 shares.
- Month 3: price $25 -> $500 buys 20.0 shares.
- Month 4: price $50 -> $500 buys 10.0 shares.
- Your cost: $2,000 spent / 52.5 shares = $38.10 per share.
Your average cost was $38.10, below the $41.25 average of the four prices.
A fixed dollar amount automatically loads up on cheap shares, no timing skill required.
FAQ
Usually not on the raw math. Because markets rise in most years, investing everything at once beats spreading it out roughly two-thirds of the time. But DCA protects you if prices fall right after you invest, and it removes the fear that keeps people out of the market entirely.
Average price is just the plain average of the prices on your buy dates. Average cost is weighted by shares: since a fixed dollar amount buys more shares when prices are low, your average cost per share ends up below the average price. That gap is the DCA advantage.
For regular paycheck investing, DCA is a permanent habit funded by your income, with no end date. For a one-time windfall, spreading it over three to twelve months is a common balance so you are not sitting in cash for too long.
No. Nobody can reliably tell a high from a pause before an even higher high, and stopping breaks the habit that makes DCA work. Keep buying the same amount; the schedule is the whole point.