US sports betting handle reached a record $166 billion in 2025 and has shown modest year-over-year gains into 2026, with eight reporting states posting $4.51 billion in September wagers, up 7.2%. Growth has slowed markedly from prior years as prediction markets such as Kalshi and Polymarket capture share, particularly among 18- to 20-year-olds and in high-volume NFL and college football betting, leading the American Gaming Association and H2 to project flat or slightly lower regulated NFL handle near $29.5–31.4 billion for the season. Mobile and in-play betting continue to dominate, with parlays driving higher operator margins even as overall volume stabilizes; Missouri’s December 2025 launch adds incremental handle while retail betting shrinks to roughly 1% of the market. Limited new-state expansion and Nebraska’s November 2026 ballot measure remain key variables for the full-year total.