In WTA tennis, spread betting — commonly referred to as game spreads or handicap betting — involves giving one player a head start or deficit in total games across a match. For example, a -4.5 game spread on a heavy favorite means she must win by at least five more games than her opponent for the bet to cash. Unlike point spreads in football or basketball, tennis spreads can behave unpredictably because of the set structure — a player can dominate one set 6-1 but lose a tight second set 7-6, dramatically shifting the game differential despite controlling most of the match.
The spreads market at the China Open becomes most valuable when there's a clear mismatch in surface suitability or form. Beijing's hard courts tend to reward aggressive baseliners and strong servers, so identifying players who thrive in those conditions but may be undervalued on the spread is key. Bettors should pay close attention to recent fatigue from the Asian swing schedule, as legs can fade quickly in later rounds, often leading to more lopsided scorelines. Vig on WTA game spreads typically runs slightly higher than on moneylines, as books build in extra margin to account for the volatility of game-level outcomes. Comparing spreads vig across books can reveal meaningful differences in value, particularly on matches further down the draw.
Analysis updated September 20, 2026. Odds data above refreshes hourly.
Spreads Vig Rankings
| # | Sportsbook | Vig | Grade | Events |
|---|---|---|---|---|
| 1 | Pinnacle | 3.43% | B+ | 16 |
| 2 | LowVig.ag | 4.33% | B | 15 |
| 3 | BetOnline.ag | 4.33% | B | 15 |
| 4 | BetAnything | 6.82% | C | 15 |
| 5 | Bovada | 6.84% | C | 24 |
| 6 | BetRivers | 7.21% | D | 24 |
| 7 | Bally Bet | 7.35% | D | 24 |
| 8 | betPARX | 7.35% | D | 24 |
| 9 | Caesars | 8.74% | D- | 24 |
| 10 | ReBet | 9.41% | D- | 24 |
Upcoming Spreads Lines
| Matchup (away @ home) | Time | ReBet | Bally Bet | betPARX | BetRivers | Pinnacle |
|---|---|---|---|---|---|---|
| Ann Li @ Ashlyn Krueger | Oct 2, 11:00 PM EDT | +1.5 (-111) | +0.5 (+114) | +0.5 (+114) | +2.5 (-120) | +1.5 (-108) |
| Maria Camila Osorio Serrano @ Coco Gauff | Oct 2, 11:00 PM EDT | -6.5 (-105) | -5.5 (-190) | -5.5 (-190) | -6.5 (-108) | -6 (-123) |
| Lin Zhu @ Donna Vekic | Oct 2, 11:00 PM EDT | -3.5 (-111) | -1.5 (-152) | -1.5 (-152) | -2.5 (-125) | -3 (-111) |
| Elise Mertens @ Katie Volynets | Oct 2, 11:00 PM EDT | +0.5 (-111) | +0.5 (-113) | +0.5 (-113) | +0.5 (-113) | +1 (-110) |
| Elina Svitolina @ Katerina Siniakova | Oct 3, 12:30 AM EDT | +5.5 (-154) | +3.5 (+145) | +3.5 (+145) | +4.5 (+100) | +5 (-121) |
Frequently Asked Questions
What is a point spread bet?
A point spread bet levels the playing field by giving the underdog a head start. If the spread is Patriots -7, they must win by more than 7 points for a spread bet to pay. Spreads are the most popular market in football and basketball, which means they attract the most volume and typically have the lowest vig.
Why do spreads usually have lower vig than moneylines?
Spreads attract the highest betting volume because they create a roughly 50/50 proposition regardless of team quality. This balanced action means sportsbooks don't need wide margins to manage risk, resulting in tighter vig — often the best value available.
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 every hour, on the hour (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 average vig: A+ (under 2%) is exchange-level pricing, A (2–3%) very competitive, B+ (3–4%) above average, B (4–5%) the industry standard, C+ (5–6%) slightly below average, C (6–7%) below average, D (7–8%) high vig, D− (8–10%) very high, F (10%+) predatory.
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, BetAnything). 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 every hour, on the hour (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.