Polymarket and Kalshi, the two largest prediction markets in the United States, have both confirmed new verified sign-up codes this week. As of Tuesday, June 23, 2026 — the opening day of Prime Day week — every Polymarket promo code is paired with a $50 bonus on a $20 deposit, for $70 total to trade, and every Kalshi promo code is a 1:1 match: spend $10, get $10, for $20 total. The verified Polymarket promo codes are CUSE, SILIVE, OREGON, MASS, and CLEVE. The verified Kalshi promo codes are SYRACUSE, SILIVE, OREGONLIVE1, MASSLIVE1, and CLEVELAND. All are confirmed active for new US accounts only.