Best Time to Visit the Derawan Islands

How to read this: Maratua Resort is an independent concierge guide — we curate and compare dive resorts and island stays in the Derawan archipelago, then arrange your booking through a vetted operating partner. We do not own or operate the resorts, and resort or brand names are used only as neutral examples, not claims of affiliation. Prices are by quote and vary by resort, season and party; figures here are indicative. Flights, transfers and dive seasons change — confirm before you travel. This is general information, not a binding offer.

The best time to visit Derawan Islands is generally the calmer, drier stretch from around March to October, when sea conditions are usually kinder for speedboat crossings and diving. That said, wildlife is present year‑round and conditions in Berau’s waters can shift by weeks each year, so the “best” time is really about matching your dates to your priorities and risk tolerance.

As Logistics & Access Editor at Maratua Resort, my job is exactly this: helping people balance weather patterns, sea state, transfers and expectations across Maratua, Derawan, Kakaban and Sangalaki. Maratua Resort itself is not a dive operator or package seller; we work as an editorial concierge, then route serious enquiries to a single vetted on‑the‑ground partner. No one can pay to change what we publish; if you proceed with our partner they may pay us a referral fee at no extra cost to you.

This guide unpacks the Derawan rainy season and dry season months, how sea conditions typically evolve through the year, and how that overlaps with the archipelago’s famous turtles, mantas and schooling fish.

How seasons work in Berau waters

Indonesia straddles the equator, so you do not get the classic four seasons. In East Kalimantan and the Derawan archipelago, you’re mostly balancing:

A drier, calmer period (broadly March–October)
A wetter, often choppier period (roughly November–February)

Local factors matter more than calendar labels. The islands sit in the Sulawesi Sea, open to swell and wind from different directions through the year. That affects:

Speedboat comfort and safety
How often crossings are delayed
Underwater visibility and surge
Ease of entering/exiting boats at jetties and dive sites

There is no monsoon shutdown like parts of Thailand or the Maldives. Resorts and homestays on Maratua, Derawan and the surrounding islands typically operate year‑round; the question is not “can I go?”, but “how much bump and rain am I willing to tolerate, and what trade‑offs am I making?”

The two main patterns

Think of the year in Derawan as:

Calmer, generally drier months (approx. March–October)
More predictable speedboat transfers Berau–Maratua/Derawan
More days with manageable chop, especially earlier and later in the period
Often better visibility for reefs and walls
Rainier, often choppier months (approx. November–February)
Higher chance of squalls and rougher seas, especially December–January
Transfers still run, but can be delayed or uncomfortably bumpy
Some dives affected by reduced vis or surge

Year to year, these lines move. Some Novembers feel like October. Some late Februaries already settle. Any “by month” guide is an informed generalisation, not a promise.

Derawan dry season months and what they mean

From a logistics and comfort perspective, the Derawan dry season months — roughly March to October — are usually the best time to visit Derawan Islands.

You won’t get zero rain for weeks on end; this is the tropics and short, intense showers are always possible. The difference is in frequency, sea state and how often plans are disrupted.

March–May: the early calmer window

Weather and sea conditions

Transition from wetter months into a more stable pattern
Increasing number of dry, sunny days
Sea conditions often moderating after the roughest spells of Dec–Feb
Still the chance of stormy days, especially early March

For diving

Reefs around Maratua, Kakaban and Sangalaki are usually in good condition after lower visitor numbers in the core rainy months
Visibility can be variable in March as waters settle, often improving through April and May
Water temperatures typically in the warm tropical range; a 3mm suit or even rash guard and shorts is enough for most divers, though some prefer more neoprene for longer or repetitive dives

For transfers

Berau to Maratua/Derawan boat rides more likely to be manageable rather than punishing
Still wise to allow some buffer time on your inbound and outbound itinerary in case of weather‑related delays

If you want calmer conditions without peak‑holiday pressure on flights and room inventory, April and May are often a sweet spot.

June–August: peak comfort for boats and families

These are typically some of the most popular months for the archipelago, especially for families restricted to school holidays.

Weather and sea

Generally settled patterns
Plenty of sun, occasional showers
Seas often at their friendliest, but you can still get windy spells

Diving

Consistently enjoyable days: stable visibility more often, less surface chop, easier entries and exits
Comfortable for newer divers and snorkellers who might be nervous in rough water
Kakaban’s jellyfish lake (when open to visitors under current regulations) is usually accessible; your operator will advise on any temporary conservation closures

Transfers

This is usually when the Berau–islands logistics feel most straightforward: fewer weather cancellations, less time juggling back‑up options
You still should not plan extremely tight same‑day onward flight connections; a few hours’ buffer is prudent in Borneo any time of year

If you prioritise smooth logistics, family‑friendly sea conditions and plenty of sun, June–August is arguably the best time to visit Derawan Islands.

September–October: calm seas, fewer crowds

As broader holiday peaks ease, September and October can deliver some of the nicest conditions with slightly quieter jetties and dive boats.

Weather and sea

Often still in the “calmer, drier” mode, though the first signs of seasonal change may appear by late October
Daytime air temperatures remain warm and humid
Sea conditions can be excellent: glassy mornings, manageable afternoon breezes

Diving

Many divers consider this one of the best periods overall: good visibility, manageable currents, reduced surface chop
Turtle activity on nesting beaches continues in various forms across the year; guides on Derawan and Sangalaki can advise what is ethically possible to see during your stay, based on current regulations and conservation practices

Transfers

Still broadly reliable, with lower probability of severe weather than mid‑rainy season
As the shoulder into the wetter months starts, keep some flexibility if you are targeting late October departures

For photographers and serious divers aiming to maximise underwater days and minimise time lost to weather, late dry‑season windows like September are often attractive.

Derawan rainy season: November–February realities

The term “Derawan rainy season” usually refers to roughly November through February. Resorts and local boats continue operating, but expect a different experience.

Rainier, choppier months by feel

November

Often a transitional month; some years still mostly fine, other years already definitively wet and windy
Afternoon squalls become more frequent
Sea state starts to deteriorate on more days, with higher chop and stronger winds

December–January

Statistically among the wetter months in East Kalimantan
Higher chance of several consecutive rainy, windy days
Sea can be rough: whitecaps, short steep chop, occasional longer swell depending on systems in the wider Sulawesi Sea
Some jetties can be lively in these conditions; boarding boats may feel athletic, especially for less mobile travellers

February

Still usually on the wetter, more unsettled side, but some years show the first more consistent improvements from mid‑month onwards

None of this means “do not travel”. It simply means you need to:

Accept a higher risk of bumpy crossings and possible schedule shuffles
Bring appropriate clothing (light rain jacket, dry bags, protection for cameras and electronics)
Maintain realistic expectations about visibility and how many dives per day are feasible in persistent bad weather

Diving in the rainy season

Underwater, the picture is nuanced.

Visibility can drop after heavy rain, especially at sites influenced by runoff or close to island shorelines. Offshore walls and seamounts may retain better clarity.
Currents are influenced by tides more than by rain itself but weather systems and swell can add complexity. This is a time to be extra‑mindful of your experience level and listen carefully to local briefings.
Surface intervals can feel cooler in windy, wet weather; a boat coat or light windproof layer makes a surprising difference to comfort between dives.

For experienced divers unfazed by some chop, the rainy season can still deliver very worthwhile dives, often with fewer other boats around the sites.

Transfers and risk management

The biggest operational challenge in the rainy season is often the speedboat transfer between Berau (Tanjung Redeb/Tanjung Batu access points) and your chosen island.

Schedules can shift based on sea state; morning departures may be moved earlier/later to catch more favourable conditions.
In very rough weather, departures may be postponed or occasionally cancelled for safety.
Sea‑sickness medication becomes more important; even confident sailors can feel it after 1–2 hours in short, sharp chop.

If you must travel in December–January — for example around year‑end holidays — build in:

At least one night in Balikpapan or Berau on arrival before any fixed activities
A buffer night on your return before any international flight
Mental flexibility: treat the archipelago as an adventure destination, not a sealed‑up, all‑weather resort corridor

If you have full date flexibility and a low tolerance for travel friction, it often makes sense to avoid the core rainy months and target the broader Mar–Oct window instead.

Derawan sea conditions by month: a practical comparison

Below is an indicative overview of how the year often feels. This is based on local patterns around Maratua, Derawan, Kakaban and Sangalaki; it should be read as guidance, not certainty.

Month	Weather tendency	Sea state for boats	Diving conditions (typical)
January	Very wet, frequent storms	Often rough; possible delays	Variable vis, more chop & surge
February	Wet, starting to ease late month	Still bumpy, improving late	Mixed vis; sensitive to weather
March	Transition to drier	Moderating; some rough days	Good diving with occasional low‑vis days
April	Generally drier	Often calm to moderate	Frequently good vis & comfortable
May	Stable, mostly dry	Usually calm	Reliable diving, enjoyable surface conditions
June	Dry, sunny spells	Calm to slight chop	Often excellent for mixed‑experience groups
July	Dry with occasional showers	Generally friendly seas	Stable vis; popular for families
August	Similar to July	Calm to moderate breezes	Consistently good diving
September	Mostly dry	Frequently calm	Many divers’ favourite window
October	Start of transition	Still fair; some windier spells	Good overall, watch late‑month shifts
November	Becoming wetter	Increasingly choppy	Mixed conditions; some very good days
December	Wettest period	Often rough, risk of delays	Variable vis, more weather interruptions

Again: this is a pattern, not a promise. Conditions for a given week in June can sometimes resemble a typical November, and vice versa.

Wildlife timing vs weather in Derawan

The Derawan archipelago is best known for:

Green and hawksbill turtles (reef encounters and nesting beaches)
Mantas around Sangalaki
Barracuda, bumphead parrotfish, sharks and schooling pelagics at Maratua’s channels and walls
Unique non‑stinging jellyfish in Kakaban’s inland lake (subject to access regulations)

Unlike some destinations where specific species appear only in very tight temporal windows, Derawan’s headline wildlife is broadly present year‑round. The interplay with seasons is more subtle.

Turtles

Resident reef turtles can be seen most months around Derawan and Maratua reefs.
Nesting and hatching cycles on certain beaches run across much of the year, with some local peaks; however, access to nesting sites and hatcheries is governed by current conservation rules, which may restrict visit times or numbers.
Better sea conditions (dry season months) make it easier for guides to safely position guests in the water for ethical, low‑stress turtle encounters on the reef.

Mantas

Sangalaki has long been associated with manta activity, though global climate patterns and shifting plankton blooms mean “guaranteed manta months” would be an overstatement.
You can encounter mantas across different parts of the year; nutrient‑rich upwellings, current strength and water clarity all play a role.
Shoulder dry‑season months (e.g. April–June, September–October) often offer a good balance of workable sea conditions and productive reef life, but no single month can be sold as a certainty.

Schooling fish and big stuff

Current‑swept sites such as channels off Maratua’s atoll structure can deliver large schools of barracuda, bumpheads and other pelagics across most months, keyed more to tide and current than strict “season”.
Strong tidal ranges occur irrespective of rain, so planning your dives around tide tables with an experienced local operator is as important as the month you visit.

If wildlife is your primary driver and you have flexible dates, the March–October band — especially April–June and September–October — typically gives you more diveable days, and therefore more chances to be in the right place at the right time.

Picking your window: how to choose when to go Derawan

Given all of the above, the “best time to visit Derawan Islands” depends heavily on your profile. A few typical scenarios:

If you want the easiest logistics

Aim for June–August, or late April–May and September.
You’ll still build in some buffer around your boat days, but you’re stacking the odds towards calmer seas and more punctual transfers.

If you’re a keen diver prioritising underwater time

Consider shoulder months like April–June and September–October.
These often give you a strong blend of manageable conditions, fewer big holiday crowds, and plenty of active marine life.

If you’re price‑sensitive

Some properties offer lower rates in the traditional “low season” periods (roughly outside major holidays), but specific numbers vary widely by property and room type and are usually available only by quote, last verified June 2026.
Remember to weigh any savings against the increased risk of weather‑related disruption, especially in December–January.

If your only option is the rainy season

November–February is viable if you go in eyes‑open: expect some rough crossings, the possibility of lost dive days, and variable visibility.
Travel with flexible expectations and a sense of adventure; treat any perfect‑blue‑day streak as a bonus, not a baseline.

Pairing Derawan with the rest of Indonesia

Many travellers pair the Derawan archipelago with other Indonesian regions (e.g. Bali, Komodo, Raja Ampat). Their peak windows don’t always line up perfectly. For instance:

Bali/Komodo: often best May–Oct
Raja Ampat: often best Oct–Apr

Derawan’s broad Mar–Oct comfort band means it pairs relatively easily with Bali or Komodo. Combining it with Raja Ampat demands a bit more compromise, usually by targeting shoulder periods where both are acceptable rather than optimal.

If you’d like a second opinion on trade‑offs for your specific dates and multi‑stop plan, you can plan your trip with us by message or WhatsApp (+62 811 3823 875). We can sanity‑check routes, overnight stops and realistic connection windows before putting you in touch with our on‑the‑ground partner for actual bookings.

What we can and cannot promise

A final word of calibration.

We cannot guarantee wildlife. Turtles, mantas, schooling fish and sharks are wild animals in a dynamic ocean. Even in “good” months, some days are quiet.
We cannot guarantee weather. Climate patterns across Indonesia have become more erratic over the last decade under El Niño/La Niña and longer‑term change. A historically dry month can receive unusual rain and vice versa.
We can help you understand risk. Choosing June over January doesn’t remove uncertainty, but it reduces certain types of risk (e.g. rough transfers).
We can connect you to one vetted operating partner. They handle live availability, personalised quotes and on‑the‑day decisions about sea state and site choice.

Our goal as Maratua Resort is to stay in the “honest guide” lane: clear about the Derawan dry season months, open about the realities of the Derawan rainy season, and upfront that the ocean runs on her own calendar.

If you’d like tailored input for your dates — or a reality check on a plan you’ve already sketched — you can plan your trip with us or message via WhatsApp on +62 811 3823 875. We’ll help you narrow down a sensible window, then step back while our partner handles the operational detail.

What is the absolute best month to visit the Derawan Islands?

There is no single perfect month, but many travellers find April–June and September particularly well balanced: generally calmer seas, usually good diving conditions, and fewer big holiday crowds than July–August. Always remember that conditions vary from year to year.

Is the Derawan rainy season a bad time to dive?

Not necessarily, but it is a higher‑risk time. November–February can still deliver excellent dives, yet you are more likely to encounter rough crossings, rain‑affected visibility and the occasional lost dive day. It can be a reasonable choice for experienced divers who accept those trade‑offs.

Are boats from Berau to Maratua and Derawan safe in the rainy season?

Local operators run these routes year‑round and generally cancel or delay departures if conditions are unsafe. However, in the rainy season crossings can be significantly rougher and less comfortable, and delays are more common, so you should avoid tight flight connections and travel with realistic expectations.

Can I see mantas and turtles all year in Derawan?

Turtles are present year‑round on the reefs, and mantas are possible in multiple months; there is no single strict “manta season”. Seasonal weather mostly influences how many days you can safely and comfortably reach the right sites rather than whether the animals exist.

How far in advance should I book for peak dry season?

For June–August and major holiday periods, securing your preferred rooms and transfer slots several months ahead is wise, especially for families or larger groups. Availability and pricing are by quote and can change, so it’s best to start the conversation early via WhatsApp or the contact page.