In WTA tennis, spread betting — commonly referred to as game handicaps — involves one player giving or receiving a specified number of games across the match. For example, a -4.5 game spread on Iga Swiatek means she needs to win by at least five more games than her opponent across all sets to cover. This differs fundamentally from team sport spreads because tennis scoring structure creates natural variance through set resets, making larger spreads harder to predict than they might appear on paper.
The spreads market becomes most valuable during the Canadian Open when there are pronounced stylistic mismatches on the hard courts of Montreal. Bettors should pay close attention to serving statistics, break point conversion rates on outdoor hard courts, and how players handle the unique conditions — including altitude and ball speed — that can amplify dominance or tighten margins. Fatigue also plays a critical role in a WTA 1000 event with compressed scheduling; early-round blowouts can give way to tighter later-round matches as accumulated fatigue sets in. Regarding vig, game spreads in WTA typically carry slightly higher juice than moneyline markets, often sitting around 5-7% compared to 3-5% on outright winner lines, making it essential to compare across books to find the sharpest available numbers.
↑ 7-day trend: WTA Canadian Open spreads average vig has worsened by 0.69 percentage points over the past week (from 5.75% to 6.44%). Odds margins are widening, meaning bettors are getting less value per wager.
Cross-Sport spreads Vig Comparison
WTA Canadian Open spreads averages 6.44% vig across 10 sportsbooks. Here's how that compares to other active sports:
| Sport | Avg Vig | vs WTA Canadian Open |
|---|---|---|
| WTA Canadian Open | 6.44% | — |
| CFL | 5.17% | 1.27% higher |
| NCAAF | 4.87% | 1.58% higher |
| NFL | 4.84% | 1.60% higher |
| NFL Preseason | 4.85% | 1.59% higher |
Vig Rankings
| # | Sportsbook | Vig | Grade | Events |
|---|---|---|---|---|
| 1 | Pinnacle | 4.51% | B | 1 |
| 2 | LowVig.ag | 4.74% | B | 1 |
| 3 | BetOnline.ag | 4.74% | B | 1 |
| 4 | betPARX | 6.41% | C | 1 |
| 5 | Bally Bet | 6.41% | C | 1 |
| 6 | BetRivers | 6.41% | C | 1 |
| 7 | Bovada | 6.93% | C | 1 |
| 8 | BetUS | 6.93% | C | 1 |
| 9 | ReBet | 8.26% | D- | 1 |
| 10 | Caesars | 9.09% | D- | 1 |
Frequently Asked Questions
Which sportsbook has the lowest WTA Canadian Open spreads vig?
Pinnacle currently has the lowest vig at 4.51%, earning a grade of B.
What is vig (vigorish) in sports betting?
Vig — short for vigorish, also called juice or overround — is the margin a sportsbook builds into its odds. It's the difference between the true probability of an outcome and what the odds imply. Lower vig means you keep more of your winnings on every bet. For example, a standard -110/-110 line has about 4.76% vig.
How often is this data updated?
We pull fresh odds from The Odds API three times per day — at 6:00 AM, 2:00 PM, and 10:00 PM UTC. Each snapshot captures the latest lines from every sportsbook that has posted odds. The timestamp at the top of the page shows the most recent refresh.
How is the vig grade calculated?
Each sportsbook is graded on a letter scale based on average vig: A+ (under 2%) is exceptional, A (2–3%) is excellent, B+ (3–4%) is above average, B (4–5%) is the industry standard, C (5–6%) is below average, and D (above 6%) indicates high-juice markets.
Why does lower vig matter for bettors?
Lower vig directly impacts your long-term returns. A bettor placing $1,000 per week at a book with 4% vig loses roughly $40/week to the house edge. At 2% vig, that drops to $20/week — a $1,040 difference over a year. For serious bettors, shopping for lower vig is one of the most reliable ways to improve profitability.
What sportsbooks do you track?
We track both regulated US sportsbooks (DraftKings, FanDuel, BetMGM, Caesars) and offshore books (Bovada, BetOnline, MyBookie, BetUS, LowVig.ag, BetAnySports). Data comes from The Odds API, which aggregates real-time lines from licensed sources.
How We Calculate These Numbers
- Data Source
- All odds on this page come from The Odds API, which aggregates real-time lines from licensed US and offshore sportsbooks. We track moneyline, spread, and totals markets across every sport with active betting lines.
- Update Frequency
- We pull a fresh snapshot of every tracked market three times per day — at 6:00 AM, 2:00 PM, and 10:00 PM UTC. Each snapshot captures the latest lines from every sportsbook that has posted odds for a given event. The timestamp at the top of each page tells you exactly when the data was last refreshed.
- Vig Calculation
- Vig (short for vigorish, also called juice or overround) measures the margin a sportsbook builds into its odds. We calculate it by converting the odds on each side of a market to implied probabilities, summing those probabilities, and subtracting 100%. For example, a market priced at -110/-110 implies 52.38% on each side — a total of 104.76%, meaning a vig of 4.76%. Lower vig means better value for bettors because you keep more of your winnings.
- Per-Market Breakdown
- We compute vig separately for each market type: moneyline (h2h), point spreads, and totals (over/under). The "average vig" shown for each sportsbook is the mean across all market types weighted by the number of events sampled in each market.
- Grading Scale
- Every sportsbook receives a letter grade based on its average vig: A+ (under 2%) is exchange-level pricing. A (2–3%) is very competitive. B+ (3–4%) is above average. B (4–5%) is the industry standard — a -110/-110 line is 4.76%. C+ (5–6%) is slightly below average. C (6–7%) is below average. D (7–8%) is high vig. D− (8–10%) is very high vig. F (10%+) is predatory pricing. See the full Vig Index Methodology for formulas, worked examples, and known limitations.
- Trend Tracking
- We store daily snapshots for 30 days, allowing us to show 24-hour and 7-day vig trends. A downward trend (improving) means sportsbooks are tightening their lines — often in response to increased competition or higher betting volume as a season heats up.