Reduced juice is the sportsbook charging you less vig on every bet. That's it. No bonus wagering, no promo tab, no clock. Just a smaller cut, forever, on every wager you place with that book.
Standard US pricing is -110 on both sides of a point spread or a total. The 10 you pay above even money is the book's cut, and it works out to a 4.55% hold. Reduced juice books price the same market at -105 on both sides. The cut is roughly 2.38%, or about half. On the same $100 bet, one book takes $10 out of the pot. The other takes about $5. That difference sits with you or it sits with the desk.
A $500 sign-up bonus is a one-time credit with a rollover. Reduced juice is the ticket price on every bet you ever make, for as long as your account is open. Bet twice a week for a year and reduced juice quietly outperforms almost any welcome offer. The math is in the reduced juice vs bonus comparison.
On our list, Bet105 is the only book pricing NFL, NBA, MLB, NHL, MMA and college football at -105 on both sides across most markets. See the reduced juice explainer for how the pricing shows up in practice, and the best NFL book for how it compares.
Reduced juice books tend to have thinner welcome bonuses. That is the trade. You are choosing a smaller one-time incentive in exchange for a lower cut on every bet. If you plan to place more than a few dozen bets, the second deal is worth more. If you plan to deposit once, take a free bet, and disappear, the first deal is worth more.