Ocean Marina Jomtien became Thailand's largest pleasure-craft harbor in 2009, anchoring a 35-hectare complex that displaced the old fishing wharves and establishing Pattaya as Southeast Asia's fastest-growing yacht-charter corridor. By 2026 the marina berths more than 400 vessels, ranging from twelve-meter day cruisers to twin-hull catamarans purpose-built for group island circuits. The shift from crewed sailing to party-platform yachting began around 2015, when tour operators noticed demand for turnkey social events afloat — buffet galleys, mounted sound systems, onboard photographers — rather than traditional bareboat hire. Today private yacht charters in Pattaya serve bachelor parties, corporate retreats, and milestone celebrations, most booking the three-island loop that links Koh Larn, Koh Sak, and Koh Phai within a single daylight window. The three-island itinerary traces a northeast arc across the Gulf of Thailand. Koh Larn lies seven kilometers offshore, its Tawaen and Samae beaches offering the clearest water and the densest shore infrastructure: jet-ski moorings, beach clubs, and floating swim platforms. Koh Sak, three kilometers farther, is uninhabited; its crescent bay permits anchored swimming and paddleboard deployment without competing traffic. Koh Phai, the outermost point at roughly sixteen kilometers from the marina, remains a Royal Thai Navy reservation on its northern cape, leaving the southern coral shelf open to snorkeling. Charter yachts typically anchor thirty to fifty meters offshore at each stop, deploying inflatable tenders or swim ladders. The round trip spans four to six hours of sailing, with two to three stationary intervals for swimming, lunch service, and sunbathing. Pattaya's private yacht party tours operate year-round, though the November-to-February northeast monsoon brings calmer seas and lower humidity. Afternoon departures capture the westward sun descent, and most sunset cruises schedule DJ sets to begin after the third island anchorage, when the yacht turns back toward Jomtien under dimming light. Buffet catering is standard: grilled seafood, green papaya salad, fried rice, seasonal fruit platters. Catamarans, with their twin-hull stability and wide foredeck nets, dominate the private-charter segment; their beam width allows simultaneous serving stations, loungers, and a raised helm deck that doubles as a DJ booth. Monohull yachts appeal to smaller groups seeking the traditional heel and keel feel, though they lack the deck acreage that defines the modern yacht party format. Ocean Marina Jomtien enforces an 08:00 earliest departure window, aligning with tidal access and crew shift schedules. Late-morning and early-afternoon slots remain the most requested, positioning the return leg to coincide with the golden hour. Free cancellation policies extend up to 24 hours before departure across most charter operators, reflecting the weather volatility that can ground vessels during the May-to-October southwest monsoon.