When looking to bet an individual basketball or football
game against the spread, you will traditionally have
odds of -110. That is the industry standard. In some
circumstances, oddsmakers will shade the vig (i.e. the
"juice") toward one team to attract some bets toward a
certain side and help them balance their books. For
example, 3 is a very important number in football
because more games finish with a winning margin of 3
points than any other potential outcome. Oddsmakers are
very careful with creating point spreads around the
number 3 because of how often games end with a 3-point
margin. So instead of moving the point spread from -3 to
-2.5 or -3.5, oddsmakers will keep the spread at -3 and
shift the odds from -110 on each side to -105/-115 or
+100/-120.
The reason oddsmakers are so careful with moving the
"juice" and not moving the actual point spread is
because they don't want to get middled. Middling occurs
when groups who bet on the favorite AND the underdog at
different point spreads both win. If Group A bets on the
favorite at -2.5 and two days later the spread is up to
3.5, Group B swoops in to take the underdog at +3.5. If
the game ends 17-14, both groups have just won.
If you are serious about taking sports betting beyond a
fun, recreational hobby, it's important to have access
to multiple sports books, if possible. Making sure that
you are getting the best numbers at the best odds will
help you become a profitable long-term bettor.