Which console was the first to include a built-in modem as standard equipment?

Sega Dreamcast was the first console to include a built-in modem as standard equipment.

Sega launched the Dreamcast in Japan in November 1998 and in North America in September 1999. Japanese and North American versions included a 56 kbit/s dial-up modem, allowing players to connect to online services without buying a separate accessory. The European model generally used a slower 33.6 kbit/s modem.

The Dreamcast’s online features included web browsing, downloadable content, online play, and SegaNet in North America. Games such as ChuChu Rocket!, Quake III Arena, and Phantasy Star Online demonstrated different approaches to console multiplayer and network services.

The Dreamcast was not the first console to support online gaming: earlier systems could connect through optional modems or other devices. Its distinction was making the modem part of the standard console package. Sega discontinued the Dreamcast in 2001, but its built-in networking helped influence later online-focused consoles.