MLB Betting Promos for Wednesday, August 12: Claim Bonuses for Mariners-Yankees on ESPN

Best MLB Betting Promos for Wednesday, August 12

Each offer below has been checked and is live for today's MLB slate. Here's the payout, the buy-in that triggers it and the code that unlocks it.

1. Fanatics Sportsbook Promo Code

The Fanatics Sportsbook promo codeACTION26 hands new users a $1,000 Bet Match stretched over ten consecutive days of wagering, which makes it the offer built for repeat action rather than one big swing. Any losing wager on a given day comes back as FanCash, so the safety net resets every morning.

With the Mariners and Yankees opening a series in the Bronx, that ten-day runway lines up with the full set instead of a single qualifier.

2. BetMGM Bonus Code

The BetMGM bonus code TOPACTION owns the largest headline figure on this page: up to $1,500 of protection on your first wager. Aim it at the Mariners as road underdogs, a Yankee Stadium total, an Aaron Judge home run prop — the market doesn't matter.

If the opener loses, BetMGM sends the stake back in bonus bets up to that $1,500 ceiling, so the size of your first bet determines how much of the offer you actually use.

3. bet365 Bonus Code

There's nothing to type in for the bet365 bonus code, as registering through our link attaches the offer automatically. The terms are as clean as MLB betting promos come: risk $10 on any market tonight and $150 in bonus bets lands regardless of the outcome.

Put it on Bryce Miller's strikeout total, the Yankees moneyline or a late Rangers-Angels side; a loss pays the same as a win here.

4. DraftKings Promo Code

The DraftKings promo code activates through the link alone, and it carries the lowest entry price on this page. Five dollars on any market returns $150 in bonus bets, credited the moment the wager is placed rather than after it grades.

If you want funded bonus bets in hand before the 7 p.m. ET first pitch in the Bronx, this is the best option among Wednesday's MLB betting promos to help you reach your destination.

5. FanDuel Promo Code

No typing required for the FanDuel promo code either, and the structure spreads your coverage across five days instead of loading it onto one bet. Wager $5 per day and each losing qualifier returns as a reset worth up to $200, capped at $1,000 overall.

For anyone betting a few dollars a night across tonight's ESPN doubleheader, that shape fits better than a single large first-bet offer.

6. theScore Bet Promo Code

theScore Bet promo code ACTNEWS opens a $1,000 First Bet Reset: back any market on tonight's card and a losing opener is refunded in bonus bets up to a grand.

The offer splits by state, though, as bettors in Michigan, New Jersey, Pennsylvania and West Virginia get a Bet $10, Get $100 bet-and-get in place of the reset. Confirm which version your account qualifies for before you fund it.

7. betPARX Promo Code

The betPARX promo code TANBONUS puts 100% insurance behind your opening wager, returned as a bonus bet worth up to $50.

It's the smallest ceiling on this page, but signup takes about two minutes, which makes it an easy add-on for Pennsylvania bettors already working down the rest of these MLB betting promos.

8. Hard Rock Bet Promo Code

The Hard Rock Bet promo code is another link-activated offer, and it's the one bet-and-get here with a string attached: the $5 first bet has to cash before the $150 in bonus bets is released.

Availability is limited to Michigan and New Jersey, and since the payout hinges on a win, a short-priced favorite like the Rangers or a heavy moneyline elsewhere on the slate is the sensible qualifier.

9. BetRivers Bonus Code

No physical code to enter here for the BetRivers bonus code, and what you receive depends on where you sign up: a 2nd Chance Bet worth as much as $500 in Michigan and Pennsylvania, scaling down to $250 in New Jersey and $100 in West Virginia.

A losing first wager comes back as a bonus bet, which keeps you in play for the late Rangers-Angels window even if the Yankee Stadium opener goes sideways.

10. Borgata Bonus Code

The Borgata bonus code ACTION closes the sportsbook list with a New Jersey-only offer. Bet $20 and $100 in bonus bets arrives as soon as the qualifier settles, no win requirement, no waiting period beyond grading.

That makes it a tidy final stop for Garden State bettors stacking Wednesday's MLB betting promos.

MLB Prediction Markets for Today's Slate

MLB betting promos aren't the only route into Mariners-Yankees and Rangers-Angels. Prediction market apps run welcome offers of their own, and their footprint stretches well past the legal sports betting states map. These alternative options are useful if you're reading this from a state where the offers above aren't available.

1. Kalshi Promo Code

The Kalshi promo code ACTION pays new traders a bonus of up to $500 once you place $25 in trades. Kalshi operates in more than 40 states, which puts tonight's Bronx opener in range for plenty of people who can't legally open a sportsbook account.

2. Polymarket Promo Code

The Polymarket promo codeACTION is the smaller of the two and the quicker to clear: deposit $10 and collect a $20 trading bonus. Coverage again runs past 40 states, so it slots in alongside Kalshi as the last bonus in your arsenal.