Comparing sportsbooks

The only sportsbook characteristic that reliably changes your long-run results is the margin built into its prices. A book running 3% margin returns roughly 97 per 100 staked to a break-even bettor; one running 7% returns 93. No sign-up bonus offsets that difference over a season.

How to compare properly

1. Pick one market you actually bet, at one moment in time.
2. Copy every outcome's price from each book.
3. Run both through the bookmaker margin calculator.
4. Compare the total implied probability. Lower is better, always.
5. Repeat across a few markets — margins vary by sport within the same book.

What to ignore

• Headline bonus size. A "€100 free bet" with 6× wagering at minimum odds is worth a fraction of its face value, and free-bet stakes are not returned.
• Odds boosts on one selection. They are marketing on a single price, usually funded by margin elsewhere in the book.
• Star ratings on affiliate sites. Rankings that correlate with commission rates tell you about the site, not the sportsbook.

What else matters

• Whether the operator is licensed in your jurisdiction.
• Withdrawal speed and whether limits are applied to winning accounts.
• Market depth for the sports you actually bet.
• Working deposit, loss and self-exclusion limits.