What is an overround in sports betting?
The short answer
The amount by which the implied probabilities of all outcomes add up to more than 100%. It is one way to express the bookmaker's built-in margin.
Odds and pricing guide
Knowing the language is step one — knowing the true price is the edge. The Cold Line’s signal desk tracks the no-vig fair number and the closing-line value behind terms like this, before the market moves.
In plain English
If both sides of a bet add up to more than 100% chance, that extra is overround — the book's cushion.
What to remember about Overround
The definition
The amount by which the implied probabilities of all outcomes add up to more than 100%. It is one way to express the bookmaker's built-in margin.
In plain English
If both sides of a bet add up to more than 100% chance, that extra is overround — the book's cushion.
Example in context
−110 / −110 implies about 52.4% + 52.4% = 104.8%. Overround ≈ 4.8%.
Keep learning
Explore the next question before you place a bet.
- What is hold in sports betting?
- What is vig / vigorish / juice in sports betting?
- What is no-vig fair value in sports betting?
- What is implied probability in sports betting?
- What are american odds in sports betting?
- What is the closing line in sports betting?
- What are decimal odds in sports betting?
- What is a dime in sports betting?
Put the concept to work
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Browse the full A–Z betting glossary or read the complete betting guide. The Cold Line also publishes a free year-round sports calendar and an odds board (Free account: delayed odds).