Scuba Diving in Costa Rica

Diving in Costa Rica means big animals and two very different coasts. On the Pacific side you can drift with schooling hammerheads at Cocos Island, hang with bull sharks at the Bat Islands, and glide alongside Pacific giant mantas at the Catalinas, all fed by cool, nutrient-rich upwellings. The Caribbean side is a different world, with quieter fringing coral reefs off Cahuita and Puerto Viejo.

Why dive in Costa Rica?

• The best hammerhead diving on Earth — schooling scalloped hammerheads by the hundred over the seamounts of Cocos Island, one of the planet's great shark dives.
• Bull sharks at the Bat Islands — the only reliable place in the country to share the water with 2–3 m bull sharks, at the famous Big Scare.
• The world's largest mantas — Pacific giant mantas sweep into the Catalina Islands cleaning stations from November to May, peaking January to March.
• Two coasts, two worlds — pelagic-heavy Pacific upwellings on one side, quiet living Caribbean coral reefs off Cahuita and Puerto Viejo on the other.
• One of Earth's great conservation stories — Costa Rica protects roughly 30% of its waters, and Cocos is a declared shark sanctuary.
• Topside that rivals the diving — active volcanoes, cloud forests, sea-turtle nesting beaches, and the rainforest of Corcovado.

Where to dive in Costa Rica

Costa Rica's dive regions split between a wild, pelagic-heavy Pacific coast and a mellow Caribbean reef, so which one is right for you comes down to how far offshore you want to go and what you want to see.

Cocos Island

Looking for the big stuff, schooling hammerheads by the hundred, whale sharks, and Galapagos sharks in open blue, Cocos Island is one of the best shark dives on the planet, reachable only by a 36-hour liveaboard crossing.

Catalina Islands

The Catalina Islands are the manta playground of Guanacaste, a cluster of volcanic rock islands where Pacific giant mantas cruise the cleaning stations in the dry season, and the easygoing conditions suit divers of every level.

Bat Islands

If you want to share the water with bull sharks 2 to 3 m long at the famous Big Scare, the Bat Islands are the only place in Costa Rica to do it, on a deep, advanced dive out past the Gulf of Papagayo.

Gulf of Papagayo

Head to the Gulf of Papagayo for the most accessible diving in the country, a protected bay off Playas del Coco loaded with rays, eels, and reef fish that doubles as the launch point for the Catalinas and Bat Islands.

Caño Island

Caño Island is the all-rounder of the southern Pacific, a biological reserve off the Osa Peninsula with the clearest water in the country and a cast of reef sharks, turtles, and seasonal mantas on a single two-tank dive.

Caribbean Coast

For a slower pace and living coral, the Caribbean coast around Cahuita and Puerto Viejo protects the largest reef on this side of the country, at its best in the September-to-October window when the water goes glassy.

Best time to dive

Costa Rica's two coasts run on opposite calendars. On the Pacific, the dry season from December to April brings the best visibility (around 15 to 25 m / 50 to 82 ft) and the migratory Pacific giant mantas to the Catalinas (they show up from November to May, peaking January to March), while the green season from May to November warms the water and delivers the bull sharks at the Bat Islands. The Caribbean flips the script entirely, with its clearest, calmest diving landing in September and October when the rest of the country is at its wettest.

Diving conditions

• Water temperature: 24–30 °C (75–86 °F), though thermoclines on deeper Pacific dives can plunge as low as 17 °C (63 °F), so pack a 5 mm suit
• Visibility: best on the Pacific in the dry season at around 15–25 m (50–82 ft); the Caribbean is clearest in September–October
• Currents: strong at the pelagic Pacific sites like Cocos and the Bat Islands; gentler in the Gulf of Papagayo and on the Caribbean reef
• Seasons by coast: the Pacific peaks December–April for mantas and May–November for bull sharks; the Caribbean peaks September–October

Marine life highlights

Costa Rica sits in the Eastern Tropical Pacific, a corridor where deep-water upwellings pull in large pelagics, which is why the country is defined by its sharks and rays rather than its coral. The Pacific delivers the headline encounters, while the small Caribbean reef adds gentler species like angelfish and hawksbills. Here's what divers travel for and where to find it.

• Scalloped hammerhead — schools of hundreds gather over the seamounts at Cocos Island, biggest in the rainy season from June to November.
• Bull shark — the Bat Islands are the only reliable spot in the country, with peak aggregations of 10 to 20 animals from June through October.
• Pacific giant manta — the largest mantas in the world sweep into the Catalina Islands cleaning stations from November to May, peaking January to March.
• Whitetip reef shark — a year-round resident across the Pacific sites, piling onto the reef at Caño Island and the Catalinas.
• Humpback whale — the South Pacific around Caño Island and the Osa hosts one of the longest humpback seasons on Earth, drawing both southern-hemisphere whales (roughly July to October) and northern-hemisphere whales (December to March), with song often audible underwater.
• Sea turtles — green and hawksbill turtles on the reefs, plus olive ridley and leatherback nesting on nearby beaches.
• Whale shark — an occasional but electrifying visitor to the Bat Islands and the Gulf of Papagayo.

Conservation

Costa Rica is one of the world's marine-conservation leaders. In December 2021 the country expanded Cocos Island National Park to 27 times its former size and folded it into the new Bicentennial Marine Managed Area, which pushed protection from around 2.7% of national waters to roughly 30%, with no-take zones shielding the underwater seamounts that hold some of the planet's densest shark populations. Cocos is a declared shark sanctuary, and groups like MarViva, Fins Attached, and the Turtle Island Restoration Network run research and anti-poaching work you can support.

How you can help: Choose operators that fund conservation, follow strict no-touch and no-glove rules on the reef, wear reef-safe sunscreen, and log your shark and ray sightings for citizen-science databases. Read more about Divearoo's Conservation First policies.

Costa Rica culture — other reasons to go

Costa Rica makes it easy to build a trip around your dives, because the best land adventures sit right next to the main dive bases. Fly into Guanacaste for the Pacific diving and you are a short drive from Rincón de la Vieja, a steaming active volcano ringed by hot springs, mud pots, and waterfall trails. La Fortuna and the cone of Arenal Volcano, with its thermal rivers, are an easy add-on. This is also turtle country, with olive ridleys arriving to nest on beaches like Ostional and leatherbacks hauling out at Playa Grande. Head south to dive Caño Island and you are on the doorstep of Corcovado, one of the most biologically intense rainforests anywhere, where scarlet macaws, tapirs, and four monkey species share the trails. Everywhere you go, the pura vida pace and a plate of casado (rice, beans, plantain, and fresh fish) keep things laid-back.

• Rincón de la Vieja National Park — an active volcano with hot springs and waterfall hikes, under two hours from the Guanacaste dive towns.
• Arenal Volcano and La Fortuna — thermal baths, hanging bridges, and one of the country's most iconic volcano views for a non-diving day.
• Sea turtle nesting — time your trip for an olive ridley arribada at Ostional or leatherbacks at Playa Grande on the Pacific.
• Corcovado National Park — pair Caño Island with a guided hike through the Osa Peninsula's world-class rainforest.
• Tamarindo surf and sunsets — learn to surf or just watch the sun drop with a catamaran cruise between dive days.
• Coffee and chocolate tours — sample Costa Rica's two most famous crops on a rainy-afternoon farm visit.

Getting there and costs

Costa Rica is solid value for the diving on offer. A local two-tank boat dive in Guanacaste runs about $90–140 USD, day trips to the Catalina Islands land around $120–180 USD (the Bat Islands often run higher, $150–200+ USD, given the longer boat ride), and a Cocos Island liveaboard is a different tier at roughly $5,000–8,000 USD for an 8–10 day expedition. Call the country $$ for day diving and $$$$ once you factor in a Cocos trip.

Most divers won't need a visa. Citizens of the US, UK, EU, Australia, and New Zealand enter visa-free as tourists for up to 90 days (US visitors can now stay up to 180), provided you can show proof of onward travel and enough funds for your stay. There's no tourist entry card fee, but a departure tax of around $29 applies (usually bundled into your airfare). Budget separately for park and reserve fees: Caño Island charges a biological-reserve entry fee, most national parks charge a per-person entry, and the Cocos Island marine park fee runs roughly $525 to $554, scaled to your number of diving days.