Ask any diver about their bucket list, and Raja Ampat usually comes up within the first few breaths. Tucked away in the far east of Indonesia, this scattering of islands has been called the most biodiverse marine region on Earth. Walls coated in soft corals, enormous schools of fish, pygmy seahorses the size of your fingernail, and mantas with wingspans longer than a car, it’s all here.
The best part? You can dive Raja Ampat almost all year. The only exception is June and July, when the winds pick up and conditions at sea are less predictable. Outside of that brief pause, you can count on world-class diving whenever you come.
That said, each month has its own personality. Here’s a breakdown of what you might find if you join La Galigo Liveaboard in Raja Ampat, from the quieter off-season through to the busiest manta months.
August: A Quiet Restart
After two windier months, things begin to settle in August. Conditions aren’t as silky smooth as later in the year, but sheltered areas around Gam, Waigeo, and the central Dampier Strait are usually diveable.
Why go: Fewer boats are operating, so reefs feel empty. Macro lovers will enjoy clearer water and calmer critters, perfect for nudibranchs, pygmy seahorses, and ghost pipefish.
Conditions: Some wind and chop remain on exposed crossings; visibility varies, but 12–18 m is normal.
Highlights: A month to explore Raja Ampat without the crowds, and often at better value.
September: The Calm Before the Peak
By September, the seas are calming down and visibility improves with every passing week. It’s the start of the shoulder season, so dive sites are still uncrowded.
Why go: A good mix of schools of fish, healthy reefs, and the first chance of spotting a manta.
Conditions: Seas flatten out, vis climbs to 20 m or more. Mostly sunny, with occasional showers.
Highlights: Excellent for photographers thanks to both schooling fish and easier currents.
October: The Season Opens
October feels like a fresh breath of air, blue skies, flat seas, and the official start of the main diving season.
Why go: The first big manta sightings usually begin now, particularly at cleaning stations in Dampier Strait.
Conditions: Calm seas, clear visibility (20–25 m), and warm 29°C water.
Highlights: Both Misool and Dampier Strait are accessible, making October one of the most flexible months to explore.
November: Manta Encounters
By November, Raja Ampat really shows off. Plankton blooms draw in mantas in larger numbers, and the reefs are buzzing with life.
Why go: High chance of manta trains and barrel-rolling displays. Pelagic fish action is excellent too.
Conditions: Visibility often 25 m+, calm seas, occasional short rain showers.
Highlights: Peak season without peak crowds, a sweet spot for divers who want both marine action and a bit of elbow room.
December: Festive Season, Underwater and Onboard
December is lively both in and out of the water. Many divers choose to spend the holidays in Raja Ampat, so there’s a festive spirit aboard liveaboards.
Why go: Still peak manta season, plus shark activity is strong, with plenty of blacktips and whitetips patrolling reefs.
Conditions: Mostly calm seas; occasional heavy showers but they rarely affect diving.
Highlights: A magical time to end the year, with big schools of fish and giant mantas overhead.
January: Raja Ampat at Its Best
January is often described as Raja Ampat’s prime month. Everything seems to align, weather, visibility, and marine life. It also comes after the Christmas and Ney Years festivities, so it generally tends to be more quiet.
Why go: The most reliable manta sightings, calm seas, and thriving reefs.
Conditions: Flat seas, 20–30 m visibility, 29–30°C water.
Highlights: The kind of diving that cements Raja Ampat’s reputation as one of the best places on Earth.
February: Peak Season Continues
February delivers much of what January offers, but with slightly fewer holiday crowds.
Why go: Mantas still gather in large numbers, shark encounters are consistent, and visibility remains good.
Conditions: Clear water, calm crossings, and warm seas.
Highlights: A safe bet for divers who want peak conditions without the festive-season rush.
March: Clear Water, Less Pressure
March is a favourite for underwater photographers. The water can be incredibly clear, sometimes the best of the year.
Why go: Excellent visibility, fewer liveaboards around, and a relaxed pace to diving.
Conditions: Calm seas early in the month; light rains may appear later.
Highlights: A balanced month, still plenty of action, but without the full-tilt buzz of high season.
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April: Season’s Farewell
By April, the season is winding down, but conditions are still solid, especially in the first half of the month.
Why go: Fish spawning events sometimes occur around full moons, and the reefs remain vibrant.
Conditions: Generally good, though weather becomes less predictable towards the end.
Highlights: A final chance to experience Raja Ampat before liveaboards move on for the season.
May: A Change in Rhythm
May signals the start of the wet season, but diving is still possible, especially early on.
Why go: Very quiet underwater, it feels like you have Raja Ampat to yourself.
Conditions: Increasingly mixed; calm days are interspersed with squalls.
Highlights: A month for the adventurous diver who doesn’t mind rolling with the weather.
June & July: Best Avoided
These are the only two months when diving isn’t recommended. Stronger winds and unsettled weather make conditions less predictable, which is why La Galigo Liveaboard pauses operations here. During these times it does not mean that Indonesia is not still a great place to dive. Areas such as Sangihe, Lembeh, Bangka and Halmahera remain fantastic options.
Final Thoughts
So, when’s the best time to dive Raja Ampat? The truth is it depends on what you’re after. Mantas? Aim for November to February. Clear water? March is your friend. Want the reefs to yourself? Try August or January.
No matter when you go, one thing is constant: Raja Ampat never disappoints. Onboard La Galigo Liveaboard, our crew know how to match each season with the best dive sites and experiences, whether that’s chasing mantas at Magic Mountain or drifting through clouds of fish at Cape Kri.
Whenever you decide to dive, you’ll leave with memories that stay with you forever.
