Dropping odds

Odds are not fixed. They move right up to kick-off. When odds fall noticeably, this is called dropping odds. The bookmaker then rates that outcome more likely than it did at the start. There are many reasons, for example an injury, a changed line-up, the weather or a shift in how many users are betting.

Behind the movement sits the implied probability. It is 1 divided by the odds. When the odds fall, this probability rises.

implied probability = 1 / odds

Falling odds therefore mean the provider rates the outcome more likely than before. The more the odds fall, the more clearly the view has shifted. The term dropping odds describes only the direction of the move, namely downward. When odds rise, it is the other way round, a sign that the outcome is rated less likely.

You can read more in the guide Understanding betting odds.

A set of odds starts at 2.50 and falls over the day to 1.90. This move is a set of dropping odds. The table shows how the implied probability changes as it does:

The probability rises from 40 to around 53 percent. A bet already placed keeps the odds from the moment you placed it. The move itself says nothing about the outcome. It only shows that the provider's view has changed.

Dropping odds are a hint, not proof. You should know both sides before you rely on them:

• Advantage: the move shows that new information has reached the market
• Advantage: you can see how the view shifts before kick-off
• Disadvantage: falling odds say nothing certain about the outcome
• Disadvantage: the reason for the move is often not clear
• Disadvantage: anyone who follows it blindly bets without their own view

Falling odds are therefore no reason to bet. At most they are a prompt to read up on the background to a match.

A falling set of odds rarely has just one reason. Usually several factors come together. These triggers are common:

• New info about the team: an injury, a return or a surprising line-up
• Weather situation: rain or wind can change expectations for a match
• Betting behaviour: if many users bet on the same outcome, the provider adjusts the odds
• Market alignment: the odds follow the general view of a match

It helps to tell genuine information apart from pure market movement. Odds that fall because of a confirmed injury have a different significance than odds that fall only because many users are betting on the favourite. Often you will not learn the exact reason.

Typical mistakes happen when dealing with dropping odds. These points help you:

• Look for the cause: ask yourself why the odds are falling
• Don't follow blindly: falling odds alone are not a reason to bet
• Check the context: combine the movement with your own research
• Keep to your budget: never bet just because odds are falling

Sports betting is permitted from the age of 18 (21 in Bremen). Use dropping odds as a prompt to examine a bet more closely, not as a sure signal.