Accumulators, also known as accas, parlays, or multis, are a popular form of betting where multiple selections are combined into a single wager. Each selection must win for the accumulator to pay out. The main appeal of accumulators lies in the potential for large payouts, as the odds of each selection are multiplied, leading to a much larger return compared to single bets. However, while the rewards are tempting, accumulators can also be risky for bettors.

In this article, we will discuss how the edgeand volatility shift as more events are added to an accumulator. By using average Trademate edge of 3.15% per event, we’ll show how to balance accumulators in your betting strategy to maximise profits while maintaining a reasonable level of risk.

How Adding Events Affects the Edge of an Accumulator

In an accumulator, each selection you add multiplies your edge. If you consistently select bets with a positive edge, the overall expected value (EV) of your accumulator can increase. However, as the total odd and edge increase, so does the volatility.

Let’s break this down assuming a positive edge of 3.15%, equal to Trademate average edge:

• Single Bet: Combined edge: 3.15% (1.0315)
• Two Selections: Combined edge: 6.31% (1.0315 × 1.0315 = 1.0631)
• Three Selections: Combined edge: 9.56% (1.0315 × 1.0315 × 1.0315 = 1.0956)

and so on…

This graph shows how the combined edge increases as the number of selections in an accumulator grows.

As more events are added, the combined edge rises exponentially, reaching 36% with 10 selections and 86% with 20 selections! While the advantage compounds with each additional selection, risk and volatility exponentially increase too.

It's crucial to understand that for accumulators to be advantageous, each bet within the accumulator must have a positive edge. If a bet lacks an edge, you're effectively increasing the bookmaker's advantage with every additional selection. For example, imagine that instead of a positive 3.15% edge, each event carries a negative 3.15% edge. By combining 5 such bets, your overall negative edge would increase to -14.79%; with 10 bets, it would grow to -27.39%, and with 20 bets, it would reach -47.28%.

The Catch: Increased Volatility and Risk

As you add more selections to an accumulator, your edge increases, but so does volatility. The more selections you include in your accumulator, the harder it becomes to win because all selections must be correct for the bet to succeed. If even one selection loses, the entire accumulator fails. Therefore, while your long-term edge improves with more selections, the probability of winning the entire bet decreases significantly.

Let’s look at an example where each selection has odds of 2.00 and a 3.15% edge, equal to the Trademate average. Normally, odds of 2.00 represent an implied probability of 50%. However, with a 3.15% edge, the actual probability of that event occurring is slightly higher than what the odds imply, around 53%. This means that, although the bookmaker's odds suggest a 50% chance, the true probability of each event in the accumulator happening is 53%.

This graph illustrates how the probability of winning drops as the number of selections increases. Once the number of selections goes beyond 5 or 6, the chances of winning become significantly lower.

For this reason, despite the potential edge offered by accumulators, it's generally advisable not to include more than 3 or 4 selections (depending on the likelihood of each events outcome) in your accumulator to reduce variance. Even with a solid edge, accumulators can lead to long-losing streaks before you finally hit a big win. This means you'll need to be prepared for more losses along the way and manage your bankroll carefully to handle the ups and downs.

A Hidden Benefit: Reduced Risk of Getting Limited

One often overlooked benefit of placing accumulators is that bookmakers are less likely to limit your account compared to when you place single bets with a consistent edge. Bookmakers are usually quick to spot and limit sharp bettors who repeatedly place value bets on single selections. However, when you place accumulators, the high variance and increased risk mask your long-term profitability, allowing you to continue betting without drawing as much attention.

Since accumulators carry more inherent risk and have a lower probability of winning (despite a positive edge), bookmakers view them as less threatening to their profits. This makes accumulators a strategic option if you’re trying to avoid account limitations while still taking advantage of a positive edge.

How to Approach Accumulators Wisely

Given the higher risk that accumulators carry, they need to be approached with caution when value betting. My favorite approach is a balanced betting strategy that combines both single bets and accumulators with a low number of selections. Single bets provide more consistent and stable returns, while accumulators offer the opportunity for larger payouts. By integrating both approaches, you can enjoy the benefits of higher expected value (EV) from accumulators, while reducing overall volatility with single bets. Furthermore, placing accumulators lowers the chances of being limited by bookmakers, as their longer odds and higher variance attract less attention compared to consistently profitable single bets.

Managing your bankroll is equally important when dealing with accumulators. Since these bets carry more inherent risk than single bets, it’s advisable to wager smaller amounts relative to your total bankroll. This strategy ensures that you can handle the inevitable losing streaks, which are more common with high-variance bets like accumulators.

By carefully managing your stake size and adopting a balanced strategy, you can optimize long-term profitability and make accumulators a valuable tool.