Editorial team: What does a 25% profit boost do to -220 odds?

A 25% profit boost on -220 odds makes the profit part 25% larger. It does not add 25% to the stake.

For -220, the unboosted profit on 1 unit is:

100 / 220 = 0.454545... units

Apply the boost to profit only:

0.454545... × 1.25 = 0.5681818...

So the boosted decimal return is:

1 + 0.5681818... = 1.5681818...

That is equivalent to about -176 American odds because the profit is still less than 1 unit per unit staked. Operator help pages commonly define profit boosts as increasing the profit on a winning outcome, while availability and promotion rules depend on the specific offer and jurisdiction: https://support.draftkings.com/dk/en-ca/how-do-i-apply-a-boost?id=kb_article_view&sysparm_article=KB0010436

Hypothetical $100 example

Method: convert negative American odds to profit per unit, multiply only that profit by 1.25, then add the original stake back for total return. You can check the same arithmetic with the ToolsGambling profit boost calculator: https://toolsgambling.com/betting/profit-boost-calculator

Assumptions: uncapped boost, winning settlement, no fees, no cash-out adjustment and no special operator rule. Real promotions can have maximum stakes, excluded markets, opt-in requirements or different settlement wording. This is arithmetic, not a claim that any current operator offer is available or valuable.