Scuba diving in Costa Rica is the best way to experience the country’s ‘Rich Coast.’ Costa Rican waters, especially on the Pacific side are teeming with life, fed by the nutritious west coast currents and plankton blooms. Large animals like whales migrate through Costa Rica’s Pacific waters, along with manta rays, dolphins, turtles, and lots of sharks. There’s more to diving in Costa Rica than the world-famous Cocos Island, whose schools of hammerheads are world-renowned. Guanacaste and Puntarenas regions also have plenty to offer, as do the clear waters of the Caribbean coast.

There are lots of dive shops to choose from in Guanacaste and Puntarenas, where visitors can fun dive, learn to dive or acquire additional specialty certifications. To get to Cocos Island, divers must choose one of the experienced liveaboard fleets, which specialize in keeping passengers comfortable during the 36-hour crossing. For nature-lovers who want to add land tours to their dive holiday, Costa Rica is the perfect choice of Central American countries. Twenty-five percent of Costa Rican land is protected, so you can visit rainforests, cloud forests and rivers, and enjoy hot springs, rafting, ziplining and canopy tours. Costa Rica is also a surfing destination.
 

The best time of year to dive in Costa Rica depends on what you’re looking for. Along the Pacific coast, the dry season is December through April and the rainy season is May through November. It usually rains for a couple of hours each afternoon during rainy season. However, rainy season is considered much better for certain dive experiences, because the season’s plankton bloom attracts many big animals.

The best time to see hammerheads, mantas, and whale sharks at Cocos Island is June through September, even though the crossing from the mainland can be rough. If you're susceptible to seasickness, you might consider looking for a Cocos tour during the dry season.

See bull sharks in the Bat Islands is during the rainy season, from May through November. The islands are not reachable from December through March because of local, gale-force ‘Papagayo winds.’

Mantas can be seen in the Catalina Islands from November through May, but the islands can be dived all year-round. On the other hand, Herradura to the south is only open for diving during the dry season from December through April.

The best time to dive Costa Rica’s Caribbean coast is during the local dry season, from February to September.

Visibility in Costa Rican dive sites improves with the distance from shore, since there are many rivers in Costa Rica. It usually ranges from 10 to 30 meters. The temperature has a wide range as well, from 20 C or 70 F to 29 C or 84 F. Dramatic thermoclines are common all over the country.

Costa Rica diving is mostly about seeing big animals and abundant marine life. The rocky landscape on the Pacific side is not colorful or diverse. However, the Caribbean dive sites in Costa Rica are full of colorful coral reefs.

Most diving in Costa Rica can be organized from land-based dive centers. However, a dive liveaboard is the only way to reach Cocos Island, and some liveaboards also travel to Cano in order to spend extra time at all its excellent dive sites. Seamounts and volcanic islands offer good opportunities for wall diving and drift diving, and provide interesting caverns to explore. There are also a few wrecks in Costa Rican waters which lie within recreational diving limits.

Costa Rica specializes in big marine wildlife. It is one of the premier dive locations to see schooling scalloped hammerhead sharks, found off Cocos Island. Also at Cocos, divers will likely encounter whale sharks, marlin, sailfish, Galapagos sharks, and silky sharks. Whale sharks can also be seen at Cano, the Catalinas, and other Costa Rica dive sites with luck. In the Bat Islands, the mighty bull shark is the local dive specialty; they are massive and undisturbed by humans in this area, with no chum, bait, or other feeding tactics.

Other reef species in Costa Rica include barracuda, schools of snapper, spadefish, grunts, jacks, eagle rays, mobula rays, moray eels, and huge lobsters. One of the most special things about the Costa Rican marine environment is the amount of dolphins and whales who call it their home. Costa Rica enjoys the longest humpback whale season in the entire world, from December to April and July to November. Also enjoying Costa Rica’s productive waters are false killer whale and pilot whales, as well as resident populations of spinner, spotted, and bottlenose dolphins. Divers in Costa Rica will likely see some of these intelligent, awe-inspiring creatures on the way to their dive sites, but it’s also worth considering a dedicated whale- or dolphin-watching tour.

Costa Rica is also home to four sea turtle species, some of them critically endangered: the four species are the leatherback, hawksbill, green, and olive ridley. The turtles use the ocean to eat and breed and the beaches to lay their eggs. Costa Rica holds dozens of critical nesting areas, many of which are monitored and protected by noble volunteer efforts.

Cocos Island

Probably the best known place to scuba dive in Costa Rica is unquestionably Cocos Island National Park, a UNESCO World Heritage Site. This lush island of green trees and gushing waterfalls lies 550 kilometers off Costa Rica’s west coast. Its most famous dive site is Bajo Alcyone, a seamount with cleaning stations which draw manta rays, whale sharks, and hundreds of scalloped hammerheads. Shark-lovers will jump at the opportunity to see other rarely-encountered species like galapagos sharks, silky sharks, and tiger sharks.

Guanacaste

Guanacaste in the north is the province which includes the Catalina Islands and the Bat Islands (their local name is Isla Murcielago). From the town of Playas del Coco, trips can depart for either area. At the Bats dive site Big Scare, divers brave the strong currents and choppy surface conditions to look for huge bull sharks. In the Catalinas, divers can find oceanic manta rays, as well as eagle rays and stingrays. Boat trips in the Catalinas are a great part of the experience, with common visits from dolphins, humpback whales, false killer whales, and breaching mobula rays.

Caño Island

Caño Island (Isla del Caño) enjoys some of the best visibility conditions in Costa Rica, which give divers a chance to wonder at its colorful coral reefs. Whitetip reef sharks are beloved residents at Cano, and can be found resting between coral bommies on the sandy bottom. The pinnacle El Baja del Diablo is one of Cano’s premier dive sites, along with many others which can be explored via day trip or liveaboard.

Herradura is a new dive location with reliable manta sightings, whitetip sharks, a lava landscape of caverns, arches, and tunnels, and even a few wrecks.

Caribbean diving in Costa Rica offers the chance to enjoy colorful coral reefs and seagrass habitat. Special local inhabitants include turtles, dolphins, and even manatees and saltwater crocodiles. La Cahuita National Park and Gandoca Manzanillo Wildlife Refuge are two notable diving and snorkeling destinations.