MLB Opening Day Betting Promos: Score the 6 Best Sportsbook Offers for 2025 Season Now

MLB Opening Day (Thursday, March 27) has arrived, and top sportsbooks are stepping up to the plate with the best MLB betting promos for Opening Day. Whether you're looking to bet on MLB Opening Day games, season-long futures, or even MLB player props today, these MLB betting promos offer everything from bet-and-get offers to first bet promos and profit boosts — perfect for kicking off the 2025 MLB season.

There’s still time to lock in your MLB Opening Day best bets with the top MLB betting promos. Alternatively, bet on World Series odds, the MVP, and Cy Young when you sign-up with the best sportsbooks on the market today. With $4,000 in total bonus value up for grabs, now is the ideal moment to claim the best MLB betting promos for Opening Day and load up your bet slip with MLB picks for Thursday’s slate.

Check out the MLB betting promos chart below and claim your sign-up bonus before the first pitch of MLB Opening Day 2025:

MLB Betting Apps	Best MLB Betting Promos	Sign-Up Link
bet365	$1,000 First Bet Safety Net OR $150 Bet-and-Get	TOPACTION
Fanatics Sportsbook	Bet $30, Get $300 in Bonus Bets OR $1,000 in No Sweat Bets	CLICK HERE
BetMGM	Bet $10, Get $150 in Bonus Bets if You Win OR $1,600 Deposit Match	ACTIONGET
Caesars Sportsbook	Get 10 100% Profit Boost Tokens	ACTION4DYW
Underdog Fantasy	Get Up to $1,000 Bonus Cash From First Deposit	TOPACTION

Top MLB Betting Promos and Sportsbook Offers for Opening Day 2025

The best MLB betting promos for Opening Day run the gamut. Sign up now and get thousands in bonus bets for your MLB best bets today, March 27.

1. bet365

bet365 Bonus Code: TOPACTION
bet365 Sign-Up Promos: Bet $5, Get $150 in Bonus Bets, Win or Lose or $1,000 First Bet Safety Net
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

bet365 Sportsbook is stepping up to the plate this season with some of the top MLB betting promos and sportsbook offers available. New users in AZ, CO, IA, IL, IN, KY, LA, NC, NJ, OH, TN, and VA can choose between a $150 bet-and-get offer or a $1,000 First Bet Safety Net when you sign up with the bet365 bonus code TOPACTION for MLB Opening Day on Thursday, March 27.

You can opt for bet365 Sportsbook’s popular $150 bet-and-get promo. Just register with bet365 bonus code TOPACTION, place a $5+ bet on any MLB market, and get $150 in bonus bets, win or lose. It’s one of the best MLB betting promos available for Opening Day.

If you’re located in Pennsylvania, the bet-and-get promo gets even better. In addition to the $150 in bonus bets, you also receive 50 spins for bet365 Casino.

If you select the $1,000 First Bet Safety Net, place a qualifying wager at odds of -500 or longer. If your first bet doesn’t hit, bet365 refunds your entire stake in bonus bets, up to $1,000.

For example, let’s say you place a $1,000 Opening Day bet on the Toronto Blue Jays moneyline (-105) against the Baltimore Orioles. If the Blue Jays win, you receive $952.38 in profit plus your original stake. If they lose, you get $1,000 in bonus bets back to use on future MLB games, NBA action, or March Madness games tonight.

2. Fanatics Sportsbook

Fanatics Sportsbook Promo: Activate 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

The Fanatics Sportsbook promo unlocks a wide selection of MLB betting promos for Opening Day to celebrate the start of the 2025 MLB season. New users can use the Fanatics Sportsbook promo that best fits their style and state. From guaranteed bonus bets to No Sweat Bets and profit boosts, there's something for everyone looking to start their baseball betting season on the right foot.

Fanatics Sportsbook’s most popular offer — $300 Bet-and-Get Bonus (Available in AZ, CO, CT, IL, IN, LA, MA, MD, MI, NC, NJ, OH, PA, TN, VA, WV) — gives new users a total of $300 in bonus bets over their first three days:

Place a $10+ wager each day for three consecutive days
Receive $100 in bonus bets after each bet settles
Earn up to $300 total in bonus funds

With the $1,000 in No Sweat Bets offer (available in AZ, CO, CT, DC, IA, IL, IN, KS, KY, LA, MA, MD, MI, NC, NJ, OH, PA, TN, VA, VT, WV, WY), Fanatics Sportsbook gives you up to $100 in no Sweat Bets each day for 10 straight days. If your qualifying wager loses, you get up to $100 in bonus bets back. That’s up to $1,000 in bonus bets available, giving you peace of mind as you bet on Opening Day MLB games.

New York bettors can triple their winnings on Opening Day, thanks to an exclusive 300% Profit Boost Token:

Sign up now and wager up to $50 on any MLB Opening Day market
If your bet wins, your profit is tripled, giving you a huge return on a single bet 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

Now that MLB Opening Day is here, BetMGM Sportsbook is offering some of the best MLB betting promos to help new users start the 2025 baseball season with a boost. Whether you’re aiming to cash in on bonus bets, secure a deposit match, or protect your first wager, there’s a BetMGM bonus code designed to fit your betting style.

Sign up using the BetMGM bonus code ACTIONGET to claim a bet $10, win $150 in bonus bets offer (available in CO, MI, NJ, PA, and WV). Register now and place a $10+ bet on any MLB market, and if your first wager wins, you receive $150 in bonus bets. It’s a simple and low-risk way to get a sizable bonus to use for MLB Opening Day and beyond.

Use BetMGM bonus code TOPTAN1600 when you register to receive a 20% deposit match up to $1,600 in AZ, CO, DC, IN, IA, KS, KY, MA, MD, MI, NJ, NC, PA, TN, WV, and WY). While the full amount requires an $8,000 deposit, any deposit of $10 or more qualifies you for bonus funds, giving you more flexibility for daily bets and MLB futures.

Planning to place a bigger MLB Opening Day wager? Sign up with BetMGM bonus code TOPACTION and claim a $1,500 first bet offer (available in AZ, DC, IA, IL, IN, LA, KS, KY, MA, MD, NC, OH, TN, VA, and WY). If your first bet loses, you receive your stake back in bonus bets, up to $1,500, split into five equal parts. This is a great option for MLB bettors who want to go big without risking their full bankroll on Opening Day.

4. Caesars Sportsbook

Caesars Sportsbook Promo Code: ACTION4DYW
Caesars Sportsbook Welcome Offer: 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

Doubling your profits on MLB Opening Day is easier than ever, thanks to one of the top MLB betting promos from Caesars Sportsbook. When you register using Caesars Sportsbook promo code ACTION4DYW, you receive 10 100% Profit Boost Tokens by simply placing a $1 first bet on Opening Day.

Here’s how to unlock and use your Profit Boost Tokens for MLB Opening Day now:

Place a $1 first bet on any MLB market
Instantly receive 10 100% Profit Boost Tokens
Use the profit boosts on bets up to $25 across MLB betting markets
Double your profits on any winning bet

These Profit Boost Tokens expire 14 days after they’re credited, so be sure to use them on MLB games this week.

Alternative MLB Opening Day Betting Promos

You don’t have to stick to traditional sportsbooks to get in on the MLB Opening Day action. Platforms like Kalshi and Underdog offer creative, engaging alternatives to the best MLB betting promos — whether you're into predictive markets or daily fantasy sports.

1. Kalshi Predictive Market

Kalshi Promo Code: ACTION
Kalshi Welcome Offer: Make $100 in Trades, Get $10 Sign-Up Bonus
Kalshi States Available: All 50 States + Washington D.C.

Kalshi allows you to trade on MLB outcomes instead of placing standard bets. With a format more like a futures market, you can speculate on questions like, “Who's going to be the Pro Baseball Champion?” or “Which team wins the NL East?” It’s a data-driven way to engage with MLB that adds a fresh perspective to traditional sports wagering.

How to Claim Your Kalshi Bonus:

Sign up using the Kalshi promo code ACTION
Make $100 in trades across any market
Receive a $10 bonus to continue trading and exploring

2. Underdog (DFS)

Underdog Fantasy Promo Code: TOPACTION
Underdog Fantasy Sign-Up Offer: 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

Jump into MLB Opening Day daily fantasy baseball with Underdog, where you can draft lineups or create pick’em entries featuring superstars like Aaron Judge, Juan Soto, and Shohei Ohtani. New users can claim a 50% deposit match, up to $1,000, using the Underdog Fantasy promo code TOPACTION.

Whether you're building traditional DFS lineups or testing your instincts in pick’em formats, this bonus gives you extra funds to play with all season long.