Racha Island (also called Raya Island) and Coral Island (locally known as Koh Hey) are two of the closest and most popular island escapes from Phuket — small, relatively undeveloped islands known for exceptional year-round snorkeling, calm turquoise water, and long white-sand beaches, both close enough to circumnavigate on foot.

The Islands

Coral Island (Koh Hey) — the livelier of the two, home to the Coral Beach Club with an indoor seating area, beach bar, and clean facilities including freshwater showers. Known for vibrant coral reefs and a range of water sports — clear kayaking, parasailing, banana boats, and scuba diving — alongside relaxed sunbathing.
Racha Island (Raya Island) — quieter and slightly further out, with exceptional snorkeling and diving thanks to clearer water and healthier reefs than closer-in spots. Weak currents and shallow, calm water make it ideal for snorkeling beginners and children. Popular sub-spots include Kon Kae Bay and Siam Bay for their marine life.

Timings

Departure: From Ao Chalong Pier (south Phuket), typically with morning hotel pickup; both half-day and full-day options are available year-round.
Best time to visit: Morning departures are best for calmer water and better visibility before the day heats up and crowds build, especially at Coral Island, which tends to draw more tour groups. Some operators also run sunset catamaran tours, ending the day with views over Promthep Cape as the sun sets — a nice alternative if you'd rather explore in the afternoon and finish with a sunset cruise back.
Time needed: Half-day tours run around 4–5 hours (one island only, or a shorter loop); full-day tours run 7–9 hours, giving time at both islands plus a buffet lunch, typically returning by late afternoon or sunset.
Best season: Racha and Coral Islands are a year-round destination thanks to their sheltered position, though November–April (dry season) still offers the calmest seas and clearest water.

Experiences & Highlights

Snorkeling — the main draw at both islands, with close-to-shore reefs, colorful fish, and (at Racha) notably clear water; equipment is generally provided.
Scuba diving — Racha Island is a well-regarded dive site, with options for certified divers and sometimes beginner-friendly introductory dives.
Water sports at Coral Island — parasailing, banana boats, and clear kayaking, usually available at an extra charge on-site.
Beach relaxation — long stretches of soft white sand at both islands, with sun loungers and umbrellas available (extra charge) at the main beach clubs.
Buffet lunch — most tours include a Thai lunch at a beachside restaurant, often on Coral Island.
Sunset viewing — on extended or sunset-specific tours, a stop at Promthep Cape (Phuket's famous sunset viewpoint) caps off the day.

Good to Know

Boat options: Speedboats are quickest and most common; catamaran and sailing yacht tours offer a more relaxed, scenic alternative, sometimes with added extras like fishing or a "party cruise" format with music.
Suitability: Good for families and beginner snorkelers thanks to calm, shallow water and weak currents — one of the more accessible island trips from Phuket.
Restrictions: Tours are generally not recommended for pregnant travelers or those with certain heart, bone, or blood pressure conditions, given the boat travel and swimming activities.
What to bring: Swimwear, reef-safe sunscreen, a hat, a change of clothes, and cash for optional water sports or drinks.
Good for: Travelers wanting a shorter, easier day trip than Phi Phi or the Similans, with excellent snorkeling and less overall travel time.