Saturday's MLB card runs from 1:35 p.m. ET through 8:40 p.m. ET, and the MLB prediction market promos below add bonus funds to your first trade. Six platforms open the day with sign-up offers, and each one prices contracts on every game.
FOX owns prime time with a 7:15 p.m. ET triple-header: Giants vs. Red Sox, Cubs vs. Mariners and Pirates vs. Dodgers. FS1 takes the afternoon slot with Nationals vs. Marlins at 4:10 p.m. ET.
Scan MLB odds, refresh the MLB weather report for the East Coast starts, and confirm MLB lineups once managers post them. Then grab the best prediction market promos in the table below.
| MLB Prediction Markets | MLB Prediction Market Promos | Sign-Up Link |
|---|---|---|
| Polymarket | Deposit $10, Get $20 Trading Bonus | ACTION |
| FanDuel Predicts | Sign Up & Unlock Your Offer | Click Here |
| Kalshi | Trade $25, Get $25 Bonus | ACTION |
| Novig | Deposit $10, Get $25 in Trade Credits | ACTION |
| DraftKings Predictions | Trade $5, Get $150 in Predictions Dollars | Click Here |
| ProphetX | Trade $10, Get $20 Bonus | TANBONUS |
Best MLB Prediction Market Promos for Saturday, August 22
Each of these MLB prediction market promos takes minutes to activate, and every MLB prediction market app that hosts them runs on iOS and Android.
1. Polymarket
The Polymarket promo code ACTION converts a $10 deposit into $20 in bonus funds, enough to cover a full first position on Nationals vs. Marlins.
The exchange prices single games, series outcomes, and season-long questions such as MLB MVP, so the bonus stretches well past Saturday. Players of 42 states plus Washington, DC qualify.
| Polymarket Promo Code | Polymarket Referral Bonus | Polymarket States Available |
|---|---|---|
| Polymarket Promo Code ACTION | Deposit $10, Get $20 in Bonus Funds | AL, AK, AR, CA, CO, CT, DE, FL, GA, HI, ID, IN, IA, KS, KY, LA, ME, MN, MS, MO, NE, NH, NM, NJ, NY, NC, ND, OK, OR, PA, RI, SC, SD, TN, TX, UT, VT, VA, WA, WV, WI, WY, DC |
2. FanDuel Predicts
The FanDuel Predicts promo code unlocks your welcome offer the moment registration ends, and the app pairs contract prices with the MLB odds screens FanDuel customers already navigate daily.
Coverage reaches 18 states, including Texas, Florida, Georgia, and California. Register before the 4:10 p.m. ET first pitch to trade Nationals vs. Marlins with the bonus in hand.
| FanDuel Predicts Promo Code | FanDuel Predicts Sign-Up Bonus | FanDuel Predicts States Available |
|---|---|---|
| FanDuel Predicts Promo Code (Click Here) | Sign Up & Unlock Your Offer | AK, AL, CA, DE, FL, GA, HI, ID, MN, ND, NE, NM, OK, RI, SC, SD, TX, UT |
3. Kalshi
The Kalshi promo code ACTION pays $25 in bonus money after a $25 trade, making it one of the best MLB prediction market promos.
The CFTC-regulated exchange posts win contracts on Cubs vs. Mariners and the rest of the schedule, plus markets on weather, awards, and postseason berths. 41 states and DC make the cut.
| Kalshi Promo Code | Kalshi Sign-Up Bonus | Kalshi States Available |
|---|---|---|
| Kalshi Promo Code ACTION | Trade $25, Get $25 Bonus | AL, AK, AR, CA, CO, CT, DE, FL, GA, HI, ID, IN, IA, KS, KY, LA, ME, MN, MS, MO, NE, NH, NM, NJ, NY, NC, ND, OK, OR, PA, RI, SC, SD, TN, TX, UT, VT, VA, WV, WI, WY, DC |
4. Novig
The Novig promo code ACTION turns a $10 deposit into $25 in trade credits. The peer-to-peer format hands you either side of Pirates vs. Dodgers at prices other traders set in real time.
Zero commission on winning positions separates Novig from most MLB prediction market apps. The platform serves 28 states plus DC.
| Novig Promo Code | Novig Sign-Up Bonus | Novig States Available |
|---|---|---|
| Novig Promo Code ACTION | Deposit $10, Get $25 in Trade Credits | AK, AR, FL, GA, HI, IL, IN, IA, KS, KY, ME, MA, MN, MO, NE, NH, NC, ND, OH, OK, OR, SC, SD, TX, VT, VA, DC, WI, WY |
5. DraftKings Predictions
The DraftKings Predictions promo code delivers $150 in Predictions Dollars for a $5 trade, the strongest return per dollar risked among these MLB prediction market promos.
Spend the credit on Giants vs. Red Sox at Fenway Park, then measure contract prices against live MLB odds elsewhere. Availability spans 47 states.
| DraftKings Predictions Promo Code | DraftKings Predictions Sign-Up Bonus | DraftKings Predictions States Available |
|---|---|---|
| DraftKings Predictions Promo Code (Click Here) | Trade $5, Get $150 in Predictions Dollars | AL, AK, AZ, AR, CA, CO, CT, DE, FL, GA, HI, ID, IL, IN, IA, KS, KY, LA, MD, MA, MI, MN, MS, MO, MT, NE, NV, NJ, NM, NY, NC, ND, OH, OK, OR, PA, RI, SC, SD, TN, TX, UT, VT, VA, WA, WV, WI, WY |
6. ProphetX
The ProphetX promo code TANBONUS rewards a $10 trade with a $20 bonus. The exchange matches traders directly, so prices shift as demand builds across the four-game FOX window.
ProphetX operates in 50 states, the widest footprint here, and lists MLB MVP futures alongside daily game contracts.
| ProphetX Promo Code | ProphetX Welcome Offer | ProphetX States Available |
|---|---|---|
| ProphetX Promo Code TANBONUS | Trade $10, Get $20 Bonus | AL, AK, AZ, AR, CA, CO, CT, DE, FL, GA, HI, ID, IL, IN, IA, KS, KY, LA, ME, MD, MA, MI, MN, MS, MO, MT, NE, NV, NH, NJ, NM, NY, NC, ND, OH, OK, OR, PA, RI, SC, SD, TN, TX, UT, VT, VA, WA, WV, WI, WY |
How to Claim the Best Prediction Market Apps Offers Today
- Pick a platform from the table and tap its sign-up link.
- Enter the promo code exactly as it appears, then verify your identity.
- Fund the account for at least the minimum each offer requires.
- Place your opening trade before the game locks.
Registration takes roughly five minutes on any of these MLB prediction market apps, and each one accepts debit cards, ACH transfers, and popular crypto deposits.
Stacking two or three of these MLB prediction market promos spreads bonus funds across the entire slate, from the 1:35 p.m. ET opener through the 8:40 p.m. ET finale. Confirm MLB lineups one final time, weigh the MLB weather report for the Fenway Park start, then take your position.
