Entering a Las Vegas casino in 2026 is straightforward, but strictly governed by Nevada state law. You must be at least 21 years of age to enter the gambling area or loiter near the slot machines. While most casinos don't have a "front door" checkpoint, security guards are stationed at every entrance and frequently "ID" anyone who looks under 30. You must present a valid, government-issued photo ID (like a driver's license or passport); digital IDs are becoming more accepted, but a physical backup is highly recommended. There is generally no cover charge to enter the main casino floor. Regarding attire, most casinos are very casual during the day (shorts and T-shirts are fine), but if you plan to enter high-end areas or nightclubs attached to the casino, a "Smart Casual" or "Upscale" dress code usually applies. Note that some newer properties, like Circa, are 21+ throughout the entire hotel, meaning no one under the age limit is allowed even in the lobby or restaurants.