Koh Ha offers generally safe swimming and snorkeling conditions, particularly during the dry season (November to April) when waters are calm and visibility excellent. The clear, sheltered waters around the islands are ideal for snorkeling with minimal currents in most areas. However, always snorkel with a buddy and stay aware of boat traffic, as tour boats visit regularly. Wear appropriate sun protection and consider a rash guard, as you can easily spend hours in the water. During monsoon season, conditions become rougher and tours may be cancelled. Life jackets are typically provided on tour boats and should be worn by weak swimmers.

The optimal time to visit Koh Ha is November through April during the dry season, when seas are calm, skies clear, and underwater visibility peaks at 20-30 meters. December to March represents the absolute best period with consistent conditions for snorkeling and diving. April can be hot but still excellent. May through October brings monsoon conditions with rougher seas, reduced visibility, and many tour operators suspending trips to the islands. For fewer crowds while maintaining good conditions, consider November or early December before peak tourist season. Early morning tours typically encounter calmer waters and better light for underwater photography.

Koh Ha is accessible only by boat from Trang or nearby areas. Most visitors take organized snorkeling or diving day trips from mainland Trang, with boats departing from piers like Pak Meng or Hat Yao. The journey takes approximately 1-2 hours depending on departure point and sea conditions. Tours typically combine Koh Ha with other nearby islands. Some liveaboard diving trips from Phuket or Krabi include Koh Ha in their itineraries. Private longtail boat charters can be arranged but are expensive for the distance. Advance booking with tour operators is recommended, especially during peak season when trips fill quickly.

Koh Ha is an uninhabited group of islands with no accommodation, restaurants, or facilities—part of what keeps it pristine and uncrowded. All visitors come on day trips, with most tours providing lunch (often as a picnic on the boat or beach) and drinking water. Bring additional snacks and plenty of water, especially on longer tours. The nearest accommodation is on the Trang mainland in areas like Hat Yao, Pak Meng, or Trang town, where options range from budget guesthouses to beachfront resorts. Some nearby islands like Koh Kradan and Koh Mook offer accommodation if you want an island base for exploring the region.

Koh Ha is celebrated for exceptional underwater visibility and diverse marine life, making it one of Trang's premier snorkeling destinations. The island group features vibrant coral reefs, underwater caves, and dramatic rock formations teeming with tropical fish, sea turtles, and occasional reef sharks. The clear waters often provide 20-30 meter visibility, perfect for both snorkeling and diving. Being relatively remote and less visited than famous spots like the Similan Islands, Koh Ha maintains healthier coral ecosystems and a more exclusive feel. The lack of development on the uninhabited islands preserves their natural beauty both above and below water, offering authentic wilderness experiences.