1. Phi Phi Islands
Hands down the most popular day trip from Phuket are the Phi Phi Islands. About 45-60 minutes away by speedboat from the Royal Phuket Marina, these six dazzling islands are famous for their dramatic limestone karst formations, cloaked in lush foliage, which jut from the jade-green sea. But all this beauty comes at a price. Throngs of day trippers descend on these shores every day, so if you're seeking seclusion, you won't find it here. What you will find are some famous sights such as of Maya Bay on Koh Phi Phi Ley, the location of the famous film The Beach and Koh Phi Phi Don, the archipelago's only inhabited island. Packed with resorts, this island is famous for the crab-eating macaques at Monkey Beach and the white sands of Laem Thong. Snorkeling is excellent in the crystal clear waters around the islands.
2. Phang Nga Bay
More than 100 steep, jungle-cloaked rock islands dot the clear, green waters around Phang Nga Bay, creating a breathtaking seascape that is best viewed from the water. A large area of the bay is protected as the Ao Phang Nga National Park. The most famous island is Koh Tapu (meaning Nail Island in Thai) more commonly known as James Bond Island, thanks to its distinctive top-heavy pinnacle made famous in the 1974 film The Man with the Golden Gun. Koh Ping Ghan is another popular stop and a great place to snap a photo of James Bond Island's famous rock formation. Many boat tours also include a lunch stop at the Muslim fishing village of Koh Panyee, which is home to wooden shops and homes built on stilts above the island's fringing shallow waters. Other tour highlights include swimming at Naka Island and kayaking through the limestone sea caves or Hong ("rooms") at Koh Panak and Koh Hong. Try to pick a tour that leaves in the early morning or after lunch as tourists clog the islands in the middle of the day.
3. Khao Sok National Park
About 150 kilometers from Phuket, Khao Sok National Park is a visual symphony of lush greens, deep blue lakes, waterfalls, and towering limestone peaks, all set in 738 square kilometers of one of the planet's oldest rainforests. Favorite activities here are canoeing and kayaking down the Sok River, elephant experiences, exploring bat-filled caves, and jungle trekking. Deep in the national park, man-made Cheow Lan Lake is a top attraction, with its floating raft houses and luxury tented camps. The park is home to diverse flora and fauna. Wildlife includes spectacled langurs, wild elephants, tigers, deer, boar, bear, and marbled cats, and if you're lucky, you might even spot wild gibbons swinging through the canopy. The park is also home to more than 300 species of birds including the impressive hornbill. This is one of Thailand's rainiest areas, so the best time to visit is during the dry season, from December through April.
4. Coral Island
Called Koh Hae by the locals, Coral Island lies about six kilometers southeast of Phuket and is a popular day trip destination for snorkelers and beach lovers, although the coral here has seen better days. The island is home to two lovely, but typically crowded stretches of soft, white sand: Long Beach, where many of the tour boats land, and Banana Beach, a rugged fifteen-minute walk through the jungle from the eastern end of Long Beach. The day trippers who come here love to feed the many fish that congregate in the clear water or kick out to the offshore coral reefs to snorkel with the tropical fish, including parrotfish, butterfly fish, and trumpet fish. Parasailing, kayaking, banana boat rides, and massages on the beach are other popular activities. Deck chairs are available along the shore, and you can also enjoy a meal at one of the beachfront restaurants.
5. Racha Islands
Translucent turquoise water and white sands lure crowds of day trippers to the two Racha Islands, about 12 kilometers south of Phuket. Racha Yai (Big Racha) is the most popular, with its beautiful horseshoe-shaped bay, called Ao Tawan Tok, and luxury villa-style Racha Resort. Ao Siam, the island's other large bay tends to be a little quieter. The main activities here are snorkeling and swimming in the warm, clear waters and basking on the white sands. Racha Noi (Little Racha) is uninhabited and has no tourist infrastructure, but the surrounding waters offer some decent diving. Tour boats usually depart from Chalong Pier or Rawai, and the trip takes about 45 minutes to an hour, depending on the type of boat. This day trip is often combined with a stop at Coral Island.
6. Khao Lak
On the mainland, about 80 kilometers north of Phuket, laid-back Khao Lak features about 20 kilometers of silky golden-sand beaches stretching along the north Andaman coast. On the road trip from Phuket, you'll pass through quiet little coastal towns, which seem a world away from the crowds of the big resorts. Devastated by the 2004 tsunami, much of Khao Lak has been rebuilt, and it's still a popular holiday destination in itself with a much slower pace than Phuket. You'll find many upscale, low-rise resorts and a family-friendly vibe. Day trippers will find plenty to do here. Top on the list is basking on the beautiful beaches, lapped by calm blue waters and lined with coconut palms, casuarinas, and rustic cafés. Lush mountains form a beautiful backdrop to the region, and three national parks, including Khao Sok, sprawl in the hinterland. Popular attractions and activities in the area include elephant encounters, bamboo rafting trips, waterfalls, tourist markets, and a tsunami memorial. Khao Lak is also an excellent jumping-off point to explore the relatively unspoiled Surin Islands and Similan Islands, with some of the region's best diving.
7. Mu Ko Similan National Park
About 90 kilometers offshore from Phuket, this 70-square kilometer national park encompassing eleven uninhabited islands is usually the domain of avid divers and tourists hoping to escape the huge crowds of Phang-Na Bay and the Phi Phi Islands. Despite their distance from Phuket, (more than two hours each way in a speedboat) greater numbers of day trippers are visiting the Similan Islands, and their numbers tend to swell around lunchtime. Still, the scenery is stunning; striking turquoise seas, white sand, and smooth granite boulders rim their shores, and hiking trails lead to lookouts in the lush hills behind the beaches. Sharks, rays, and vast schools of smaller fish swim in these crystal clear waters, but unfortunately some of the hard corals have been damaged by coral bleaching and the onslaught of tourist boats. Try to pick a calm day for this tour as the return boat trip can be choppy when the winds pick up, and note that the park is closed from 16th May to 31st October. In 2016, the Thai government closed one of the archipelago's most popular islands, Koh Tachai, indefinitely due to environmental damage. If you prefer a more remote outer island experience, the Surin Islands, north of the Similan Islands, are also accessible from Phuket, but it's a long day trip.
8. Koh Yao Yai
Only 20 kilometers east of Phuket (about 30 minutes by longtail boat) Koh Yao Yai ("big long island") offers Phuket day trippers a laid-back pace and a more traditional Thai vibe. Its peaceful, secluded white-sand beaches are one of its finest features; Loh Paret in particular is ideal for swimming and Laem Had beach, on Yao Yai's northeast corner, is also lovely. Rice fields, rubber plantations, and coconut groves cloak the countryside, and a single concrete road through the center of the island is the main thoroughfare. (Bicycles and motorbikes are the most popular modes of transport.) Most day trippers rent a motorbike to explore the island, stopping off to visit the little villages or take a cool dip in the sea.
9. Koh Yao Noi
Like its sister island (Koh Yao Yai) but a little more developed, Koh Yao Noi ("small long island") in Phang Nga Bay, feels like the slower-paced Thailand of 20 years ago. This island is further away from Phuket, about one hour by long tail boat, but the views of Phang Nga Bay on the way are worth the extra travel time. The locals still follow their traditional way of life here, fishing, farming, and running small shops out of rustic buildings in the Muslim village. Many travelers come here to escape the crowds of the big resorts, soak up some authentic local culture, and relax on the relatively clean palm-fringed beaches. Along the coast, you can see beautiful views of Phang Nga Bay's limestone rock formations rising from the sea.