One of the hardest questions in investing is when to buy. Wait for a dip and you may never get one. Invest everything today and you may watch prices fall next week. Pound-cost averaging, known in the US as dollar-cost averaging, is a simple way around that problem. Instead of trying to pick the perfect moment, you invest a fixed amount at regular intervals and let time do some of the work.
How it works
Say you decide to invest £200 into a fund on the first day of every month. When prices are high, your £200 buys fewer units. When prices are low, it buys more. Over time, the average price you pay per unit tends to be lower than the average market price over the same period, because you automatically buy more when things are cheaper.
Many workplace pensions and regular savings plans work this way without people realising, because contributions are invested every payday regardless of what markets are doing.
Why it helps
The biggest benefit is behavioural. Pound-cost averaging removes the pressure to time the market, which is something even professionals struggle to do consistently. It also stops you investing a large sum at the worst possible moment, which can be emotionally painful and lead to panic selling.
It suits people who are investing from regular income rather than a lump sum, and it encourages discipline. Our guide to trading discipline explains why consistency often matters more than clever timing.
Where it falls short
Pound-cost averaging does not guarantee a profit or protect against losses. If an investment falls steadily for years, buying more of it along the way still means losing money.
It can also underperform investing a lump sum all at once. Because markets have historically risen more often than they have fallen, money invested earlier has usually had more time to grow. Research by fund managers has generally found that lump-sum investing comes out ahead more often than not, although with more short-term risk of regret.
Costs matter too. If each purchase carries a fixed dealing fee, small regular investments can be eaten into. Many platforms offer cheaper regular investing options for this reason.
Is it the same as buying the dip?
Not quite. Buying the dip means waiting for prices to fall before investing, which still requires a timing decision. Pound-cost averaging is deliberately mechanical. You invest on schedule whatever the price.
Investing versus trading
Pound-cost averaging is a long-term investing technique, not a trading strategy. Applying it to leveraged products or short-term trades can be dangerous, because adding to a losing leveraged position can quickly increase your risk. Our explainer on leverage in trading covers why. It works best with diversified, long-term holdings such as broad index funds.
The beginner takeaway
If you struggle with when to invest, pound-cost averaging gives you a simple rule that takes emotion out of the decision. It will not make you rich overnight, but it can help you stay invested through volatile periods. For what is moving markets today, this morning’s Morning Market Brief has the picture. If you want to understand your own approach to risk and timing, the free Samuel & Co Trading Trader Assessment is a good place to start.
