DCA means buying an asset in equal amounts on a regular schedule, for example $100 of bitcoin every month, whatever the price is that day. The amount and the timing stay the same; only the price changes. The SEC's Investor.gov glossary describes it as a way to manage risk "by following a consistent pattern of adding new money to your investment over a long period of time." DCA does not guarantee a profit or protect against loss in a falling market, and research on stocks and bonds shows that investing a lump sum all at once has usually come out ahead.
How DCA works
You choose three things in advance:
- The amount for each purchase.
- The interval, such as weekly or monthly.
- The asset.
Then you buy on schedule without trying to judge whether the price is "right". The SEC sums up how this plays out: "By making regular investments with the same amount of money each time, you will buy more of an investment when its price is low and less of the investment when its price is high."
FINRA defines it the same way: investing "in equal portions, at regular intervals, regardless of current market conditions."
A worked example
Say you spend $100 a month on a token over four months:
| Month | Price | Amount spent | Units bought |
|---|---|---|---|
| 1 | $50 | $100 | 2 |
| 2 | $25 | $100 | 4 |
| 3 | $50 | $100 | 2 |
| 4 | $100 | $100 | 1 |
| Total | $400 | 9 |
- Average cost per unit: $400 ÷ 9 = about $44.44.
- Simple average price over the four months: ($50 + $25 + $50 + $100) ÷ 4 = $56.25.
Your average cost is lower than the average price because the fixed $100 bought more units in the cheap month. This always happens with fixed-amount buying when the price moves, because of how the arithmetic works. It is not a forecast. If the token had kept falling, you would still hold a loss.
Two uses of DCA
People use the term for two situations, and the evidence differs between them.
Investing from regular income
If you invest part of each paycheque, you are already spreading purchases over time, because the money arrives over time. In this case DCA is simply a fixed rule for money you could not have invested earlier anyway.
Spreading out a lump sum you already have
This is where the research applies. If you already hold the cash, the question is whether to invest it now or in instalments.
- The 2012 paper. Vanguard's July 2012 paper "Dollar-cost averaging just means taking risk later" (Anatoly Shtekhman, Christos Tasopoulos, Brian Wimmer) compared the two approaches in the United States, the United Kingdom and Australia. Investing the lump sum right away beat DCA roughly two-thirds of the time. The authors said DCA may suit an investor "primarily concerned with minimizing downside risk and potential feelings of regret," and noted that delaying investment is itself a form of market timing.
- The 2023 paper. Vanguard's February 2023 paper "Cost averaging: Invest now or temporarily hold your cash?" (Megan Finlay, Josef Zorn) reached the same "roughly two-thirds" conclusion. It explained the result by the fact that stocks and bonds beat cash in most periods from 1976 to 2022.
- FINRA's view is similar. It says DCA can help limit losses during sharp market falls but "often produces lower returns" than lump-sum investing, "especially over longer periods of time."
Both Vanguard studies covered traditional stock and bond portfolios, not crypto. No comparable primary study on crypto assets was checked for this article.
What does DCA make your average cost?
Enter the token price on each of four monthly buys of the same dollar amount to see your average cost per unit.
| Token price at the month 1 buy | Token price at the month 2 buy | Token price at the month 3 buy | Token price at the month 4 buy | Average cost per unit across the four buys |
|---|---|---|---|---|
| 50 $ | 25 $ | 50 $ | 100 $ | 44.44 $ |
| 50 $ | 50 $ | 50 $ | 50 $ | 50 $ |
| 100 $ | 50 $ | 25 $ | 25 $ | 36.36 $ |
- All four prices are your own inputs; the defaults repeat the article's illustrative example ($100 a month at $50, $25, $50 and $100 gives about $44.44).
- The amount spent each month is the same, so it cancels out and does not change the average cost.
- A flat price gives an average cost equal to that price; a falling price lowers the average cost but can still leave you holding a loss.
This is arithmetic on the prices you enter only: it leaves out fees, spreads and tax, does not compare DCA with investing a lump sum, and cannot predict future prices.
What DCA does and does not do
What it does:
- It takes away the need to pick a moment to buy.
- It makes it less likely that all your money goes in just before a sharp drop.
- It turns investing into a routine, which can make it easier to stick with when prices are volatile.
What it does not do:
- It does not make a weak asset a good one. If the price trends to zero, buying on a schedule only spreads out the loss.
- It does not guarantee a profit or protect against loss when prices keep falling.
- It does not beat lump-sum investing on average in the markets studied. Cash waiting to be invested misses any gains in the meantime.
- It does not remove costs. FINRA warns that more transactions can mean higher fees if you pay per trade. On small, frequent crypto purchases, a fixed fee or spread can take a noticeable share of each buy.
Practical points before you start
- Can you keep buying? DCA only works if you keep buying when prices are down. If falling prices would make you stop, the plan breaks at exactly the point it was designed for.
- Check what each purchase costs. Compare the fee and spread with the size of each purchase. Fewer, larger purchases may cost less in total than many small ones.
- Keep the uninvested balance somewhere safe. If you are spreading out a lump sum, FINRA suggests holding the rest in a low-risk, easily accessible account. It also notes that dipping into that money can derail the plan.
- Keep records of every purchase. Each purchase is a separate tax lot. For US taxpayers, the IRS says your cost basis for virtual currency is what you paid, "including fees, commissions and other acquisition costs in U.S. dollars."
- When you sell, you may choose which units you are selling if you can identify them specifically and back up their basis. - Otherwise the IRS treats units as sold on a first in, first out (FIFO) basis. - The IRS notes that these FAQs generally apply to transactions completed before 1 January 2025, so check current rules for later years.
Limitations: the research cited here covers traditional stock and bond markets, not crypto, and past results do not predict future returns.
