Today marks Opening Day of the 2025 MLB season, and you can cash in on the top sportsbook sign-up bonus offers with the best MLB betting promos. Claim your welcome bonus using these top MLB betting promos to net thousands in bonus bets now.
While it's already been a thrilling day of MLB action, Opening Day isn't over yet. Tune into the late window of games tonight, featuring the Chicago Cubs vs. Arizona Diamondbacks (10:10 p.m. ET) and Athletics vs. Seattle Mariners (10:10 p.m. ET). Sign up now with the best MLB betting promos to unlock sign-up offs from top sportsbooks like bet365, Fanatics Sportsbook, BetMGM, and Caesars Sportsbook.
Check out the latest MLB odds before registering with MLB betting promos highlighted in the chart below.
| Best MLB Sportsbooks | MLB Betting Promos for Opening Day | Sign-Up Link |
|---|---|---|
| bet365 | $150 Bet-and-Get or $1,000 First Bet Safety Net | TOPACTION |
| Fanatics Sportsbook | $300 Bet-and-Get Promo or $1,000 in No Sweat Bets | Click Here |
| BetMGM | Bet $10, Get $150 in Bonus Bets if You Win | ACTIONGET |
| Caesars Sportsbook | Bet $1, Get 10 100% Profit Boost Tokens | ACTION4DYW |
MLB Betting Promos: Top Sportsbook Sign-Up Offers for Opening Day 2025
Take advantage of these MLB betting promos for Opening Day now. But, remember, these sportsbook sin-up offers aren't only applicable to MLB. You can also use them as March Madness betting promos, perfect for the Sweet 16 NCAA Tournament games tonight.
1. bet365
- bet365 Bonus Code: TOPACTION
- bet365 Promo: $1,000 First Bet Safety Net or Bet $5, Get $150 in Bonus Bets, Win or Lose
- bet365 PA Promo: Bet $5, Get $150 in Bonus Bets + 50 Casino Spins, Win or Lose
- bet365 States Available: AZ, CO, IA, IL, IN, KY, LA, NC, NJ, OH, PA, TN, VA
Use the bet365 bonus code TOPACTION to access a $1,000 First Bet Safety Net or $150 in bonus bets. With these MLB betting promos, you must make your first bet on a market with -500 odds or longer.
Choose the First Bet Safety Net promo to place your first bet on any game. If your bet loses, bet365 returns your stake as bonus bets, up to $1,000. This sign-up bonus is available in all legal bet365 states, except Pennsylvania.
Place a $5 first bet to unlock $150 in bonus bets, win or lose, with the bet-and-get promo. Pennsylvania users get an additional perk of 50 casino spins. Don't forget to sign up for bet365 Illinois and bet365 Tennessee, as bet365 Sportsbook recently went live in each state.
2. Fanatics Sportsbook
- Fanatics Sportsbook Promo: Click Here
- Fanatics Sportsbook Bet-and-Get Promo: Bet $30, Get $300 in Bonus Bets
- Fanatics Sportsbook Sign-Up Bonus: $1,000 in No Sweat Bets
- Fanatics Sportsbook NY Sign-Up Bonus: 300% Profit Boost Token
- Fanatics Sportsbook States Available: AZ, CO, CT, DC, IA, IN, KS, KY, LA, MA, MD, MI, NJ, OH, PA, TN, VA, VT, WV, WY
Check out the top MLB betting promos for Opening Day at Fanatics Sportsbook and choose your own offer. Use the Fanatics Sportsbook promo to claim a sign-up bonus now.
Bettors in AZ, CO, CT, IL, IN, LA, MA, MD, MI, NC, NJ, OH, PA, TN, VA, WV can access $300 in bonus bets using the Fanatics Sportsbook promo. Sign up and place a $10 daily bet to receive $100 in bonus bets per day, totaling $300 over three days.
Use the Fanatics Sportsbook promo to unlock $1,000 in No Sweat Bets in the following states: AZ, CO, CT, DC, IA, IL, IN, KS, KY, LA, MA, MD, MI, NC, NJ, OH, PA, TN, VA, VT, WV, and WY. Fanatics Sportsbook offers this $1,000 across 10 days, with a daily No Sweat Bet, up to $100. If your bet loses, you get the amount back in bonus bets, up to $100.
The Fanatics Sportsbook promo in New York offers a 300% Profit Boost Token. Wager up to $50 on any baseball game today.
3. BetMGM
- BetMGM Bonus Code: ACTIONGET
- BetMGM Promo: Bet $10, Get $150 in Bonus Bets if You Win
- BetMGM Bonus Code: TOPTAN1600
- BetMGM Promo: 20% First Deposit Match, Up to $1,600 in Sports Bonus
- BetMGM Bonus Code: TOPACTION
- BetMGM Promo: $1,500 First Bet Offer
- BetMGM States Available: AZ, CO, DC, IA, IL, IN, LA, KS, KY, MA, MD, MI, NC, NJ, OH, PA, TN, VA, WV, WY
At BetMGM Sportsbook, you can access up to $1,600 in bonus value as a new sign-up. Claim these MLB betting promos at BetMGM by using the proper BetMGM bonus code featured below.
Use the BetMGM bonus code ACTIONGET and make a $10 first bet. If this bet wins, you get a payout plus $150 in bonus bets. However, a losing first bet means you won't receive $150 in bonus bets. Access this sign-up bonus in CO, MI, NJ, PA, and WV.
The BetMGM bonus code TOPTAN1600 offers a 20% deposit match, up to $1,600 in sports bonus funds. BetMGM matches 20% of your deposit in sports bonus funds, meaning you must deposit $8,000 to obtain the full $1,600 bonus. Use this BetMGM promo in AZ, CO, DC, IN, IA, KS, KY, MA, MD, MI, NJ, NC, PA, TN, WV, and WY.
Sign up using the BetMGM bonus code TOPACTION for a $1,500 first bet offer. Make your first bet on any MLB market, and you get your stake back in bonus bets, up to $1,500, if it loses. The following states can access this welcome offer: AZ, CO, DC, IA, IL, IN, LA, KS, KY, MA, MD, MI, NC, NJ, OH, PA, TN, VA, WV, and WY.
4. Caesars Sportsbook
- Caesars Sportsbook Promo Code: ACTION4DYW
- Caesars Sportsbook Welcome Bonus: Bet $1, Get 10 100% Profit Boost Tokens
- Caesars Sportsbook States Available: AZ, CO, DC, IA, IL, IN, KS, KY, LA, MA, MD, ME, MI, NC, NJ, NY, OH, ON, PA, TN, VA, WV, WY
Take advantage of one of the top MLB betting promos at Caesars Sportsbook for Opening Day now. With the Caesars Sportsbook promo code ACTION4DYW, it only takes a $1 first bet to unlock 10 100% Profit Boost Tokens instantly.
With these tokens, you can wager up to $25 on any baseball game, doubling your profit on any winning bet. Note that the Profit Boost Tokens expire after 14 days.
Sign up today to claim the Caesars Sportsbook welcome bonus in AZ, CO, DC, IA, IL, IN, KS, KY, LA, MA, MD, ME, MI, NC, NJ, NY, OH, ON, PA, TN, VA, WV, and WY.
Best Alternative Options to MLB Betting Promos for Opening Day Action
1. Kalshi Predictive Market
- Kalshi Promo Code: ACTION
- Kalshi Sign-Up Offer: Make $100 in Trades, Get $10 Sign-Up Bonus
- Kalshi States Available: All 50 States + Washington D.C.
Use the Kalshi promo code ACTION to unlock a $10 sign-up bonus. With this welcome offer, you must make $100 in trades on any market at Kalshi to access the $10 bonus. Kalshi is available nationwide, including 50 states plus Washington DC.
2. Underdog Fantasy (DFS)
- Underdog Fantasy Promo Code: TOPACTION
- Underdog Fantasy Welcome Bonus: 50% Deposit Match, Up to $1,000 in Bonus Funds
- Underdog Fantasy States Available: AL, AK, AZ, AR, CA, DC, DE, GA, IL, KS, KY, MA, MN, MO, NE, NM, NC, ND, OK, OR, RI, SC, SD, TN, TX, UT, VT, VA, WI, WV, WY
Sign up now with the Underdog Fantasy promo code TOPACTION to unlock $1,000 in bonus funds. The DFS app offers a 50% deposit match, meaning you must deposit $2,000 to claim the full $1,000 welcome bonus. Use the bonus funds to create an MLB lineup today.
MLB Opening Day Pitchers & Predictions: Night Games You Can Bet on Today
Chicago Cubs vs. Arizona Diamondbacks
- Time/Location: 10:10 p.m. ET at Chase Field (Phoenix, AZ)
- Starting Pitchers: Justin Steele (Chicago Cubs) vs. Zac Gallen (Arizona Diamondbacks)
- Prediction: Diamondbacks ML (-130)
The Diamondbacks open their season against the Cubs, who are coming off a rough start with a 0-2 record after losing both games to the Dodgers in the Tokyo series. I’m backing the Diamondbacks in tonight’s matchup, as they hold a significant pitching advantage with Zac Gallen on the mound.
If you're planning to place a bet locally, explore the top Illinois and Arizona sports betting options available for this matchup.
Athletics vs. Seattle Mariners
- Time/Location: 10:10 p.m. ET at T-Mobile Park (Seattle, Washington)
- Starting Pitchers: Luis Severino (Athletics) vs. Logan Gilbert (Seattle Mariners)
- Prediction: Mariners -1.5 (+135)
The Athletics begin a new era of baseball with an AL West matchup against the Mariners. Last season, Logan Gilbert began to establish himself as one of the best pitchers. He faces Luis Severino, who is making his first start for the Athletics after spending 10 years in New York.
I’m backing the Mariners at -1.5 (+135). Expect Gilbert to deliver a stellar performance, effectively silencing the Athletics’ bats.
Use the best MLB betting promos now and tail one of both of these MLB best bets tonight.