Scuba diving at the Great Barrier Reef: 15+ Things you need to know

The Great Barrier Reef needs no introduction.

It’s the most extensive coral reef system on earth and one of the world’s seven natural wonders. Home to over 900 islands and roughly 3,000 separate reefs, it sustains a diverse ecosystem.

Scuba diving at the Great Barrier Reef is part of every Australian travel bucket list. Featuring kaleidoscopic walls, vibrant coral, and awesome swim-throughs, it provides an underwater mecca for divers and snorkelers.

Here is everything you need to know about diving the Great Barrier Reef, including when and where to go, and how many days you need.

Scuba diving at the Great Barrier Reef
The Great Barrier Reef boasts some of the best diving in the world

There are so many places to go diving in the Great Barrier Reef

The Great Barrier Reef is massive!

It stretches more than 2,300km along Australia’s northeast coast of Queensland, starting in Bundaberg on the south and ending at the tip of Cape York on the north.

While Cairns is arguably the most popular base, there are a few major access points where you can visit the reef from.

  • Cairns is a great starting point for diving the Great Barrier Reef. It’s a short drive from Port Douglas and is close to the Daintree Rainforest, the oldest rainforest in the world. This is the Cairns itinerary I followed and includes all the best things to do (including scuba diving the Great Barrier Reef).
  • Townsville is the gateway to the central section of the reef, where you can dive from Magnetic Island and explore the SS Yongala (regarded as the world’s best wreck dive).
  • Airlie Beach is home to the Whitsundays, a cluster of spectacular islands famous for their white sand and turquoise blue waters.
  • Bundaberg lies on the Southern Great Barrier Reef. From here, you can visit Lady Elliot Island, Lady Musgrave Island, and Heron Island.
two people going to scuba dive at the Great Barrier Reef, Australia
We did 11 incredible dives over 3 days

Be prepared for unguided dives

Most Great Barrier Reef scuba diving is unguided. This means it’s only you, your dive buddy, and your trusted compass deep below the surface.

Before diving in Australia, I had only ever done guided dives. With no clue how to navigate underwater, I’d be lying if I said I wasn’t nervous!

The reality is that most people will be in the same shoes as you. But the Great Barrier Reef is a shallow reef, and it’s not as challenging as Komodo National Park in Indonesia.

Generally, your first dive is guided. This allows you to get familiar with the gear and the water conditions.

Before your unguided dive, your instructor will give a thorough briefing about the site and show you how to use a compass. If you’re feeling unsure, you can always request a guide, but you may need to pay extra for this.

Our first unguided dive was a night dive! I was totally out of my comfort zone, but it was one of the most incredible experiences.

man navigating under water
Trying to figure out how to navigate underwater

The Great Barrier Reef dive sites are uncrowded

This is a massive pro of diving the Great Barrier Reef – no crowds.

During my 3-day scuba diving liveaboard, I only saw one other boat, and they were diving at a different site to us.

Diving unguided, with only your buddy and no one else around you, is quite something and will make your experience more memorable!

Be careful of the stingers

You might be planning your Great Barrier Reef diving trip based on water visibility and weather conditions, but you must also be aware of stingers.

The most popular type of stingers in this area are box jellyfish. Their dangerous venom can be fatal to humans, and they are out in full force from November to April each year.

You can still go scuba diving at the Great Barrier Reef during stinger season but will have to wear a stinger suit. The diving companies provide these.

A school of fish in the Great Barrier Reef
No sign of stingers during the dry season

The reality of diving at the Great Barrier Reef

It’s safe to say that everyone planning on diving the Great Barrier Reef has high expectations. It’s pretty hyped up!

And while I was expecting to see more vibrant coral and bigger schools of fish (or even Grey Nurse and Leopard Sharks like you find when diving in Byron Bay), I still had incredible encounters.

My first night dive was mind-blowing, with reef sharks everywhere! They’re harmless but came pretty close to us, which was a surreal experience.

We also swam past a huge school of parrot fish, saw the biggest clams ever, and navigated through amazing swim-throughs.

But you must remember that the reef is so big, and every dive site offers a different experience. If you’re an advanced diver, you might prefer the sites closer to the reef’s northern tip or the S.S Yongala wreck dive.

Snorkeling or scuba diving the Great barrier Reef
We did a 3 day scuba diving liveaboard from Cairns

Diving the Great Barrier Reef during the wet season

While November to April is the stinger season, it is also the wet season in northern Queensland.

Tropical showers are common, and this can impact the water’s visibility. Expect hot and humid conditions as this is summer in Australia – but luckily, you’ll have the rain to cool you down.

There are a few benefits of diving in the Great Barrier Reef during the wet season.

  • The water temperatures peak at 29 degrees which is ideal. That’s a whole 7 degrees warmer than during winter!
  • It’s also quieter with fewer tourists.
  • Coral Spawning takes place in November and December.
scuba diving near Cairns
It’s Nemo!

Diving the Great Barrier Reef during the dry season

Every Great Barrier Reef diving blog you read will tell you that the best time to visit is from May to October.

This is the dry season with little to no rain and the best underwater visibility.

The temperatures hover around 26 degrees during the day, but the evenings can get chilly, reaching 17 degrees at its lowest.

Here are a few key attractions:

  • June to July: Dwarf Minke Whales
  • July to September: Humpback Whales

I was keen to dive with dwarf minke whales, so I booked my 3-day diving liveaboard for July. But I didn’t realize that these whales don’t actually hang out on the reefs that the day trips or shorter liveaboards visit.

To dive with them, you need to join a specific Minke Whale Liveaboard that goes further north to Ribbon Reef.

We also didn’t see any humpback whales, even though we were there during the annual migration. This is not to say that you won’t experience these whale encounters, but the chances aren’t likely unless you book a specific whale liveaboard dive trip.

Great Barrier Reef diving
Perfect diving conditions on the Great barrier Reef

The trade wind pick-up in June and July

June and July are the windiest months on the reef. While this won’t affect your underwater experience of diving the Great Barrier Reef, it can cause rough, windy conditions above the water.

Our trip in July was super windy, and the 3-hour ride from Cairns to the reef (and back) was pretty hectic! I quickly took a sea sickness tablet as it was very bumpy. The rough conditions died down when we got to the reef, but it was still pretty windy throughout the three days.

I had a friend who joined the same liveaboard but went a week after I did. Her experience was perfect – little to no wind. So, it really is the luck of the draw!

The best months are September and October

After speaking to a few of our dive instructors, the best months to go diving at the Great Barrier Reef are September and October.

This is the end of the winter season, so the water and outdoor temperatures are slightly warmer than in June and July. It’s also outside of the trade wind times and stinger season, so you can expect optimal conditional all round.

People standing on the top deck of a boat
It was pretty windy during our Great Barrier Reef scuba diving trip in July

Dive, sleep, eat, repeat

If you’re doing a Great Barrier Reef liveaboard, be prepared to dive, sleep, eat and repeat.

It’s full on!

And while you may be tempted to skip a dive in favor of chilling on the sundeck, try to get to all the dives on your itinerary. You never know what sightings you’ll miss out on.

Do a dive course

The Great Barrier Reef is a great place to get your diving certification. You’ll do two days of theory and skills training in Cairns before completing your open water dives on the Great Barrier Reef.

The conditions are perfect for beginner divers as there are no strong currents, the visibility is excellent, and it’s a shallow reef.

I did my Padi Advanced Course plus Nitrox certification during my liveaboard trip.

Diving in Queensland

You should do a diving liveaboard on the Great Barrier Reef

If you’re planning on diving the Great Barrier Reef from Cairns, I highly recommend joining a scuba diving liveaboard tour.

This is because the boat ride to the reef takes 1.5 to 3 hours. And then another 1.5 to 3 hours return.

Yes, you could explore the Great Barrier Reef in one day, but it will be hectic, especially during June and July when the conditions are choppy.

By doing a liveaboard, you also get the chance to do a night dive. This is a phenomenal experience, and you’ll see all those creatures that come out after dark.

liveaboard diving Great barrier Reef
Our Great Barrier Reef liveaboard

There aren’t many liveaboards to choose from

… And they get booked out fast!

I had initially booked Coral Sea Dreaming overnight liveaboard. It’s a much smaller boat and can hold an intimate group of 8 guests. The major draw card for me was that and the positive reviews.

But I eventually decided to go with Pro Dive as they offer a longer liveaboard option of 3 days. But their boat is also much bigger, and you’re diving with 30+ people on every dive!

Don’t spend much time in Cairns before your Great Barrier Reef diving trip

Cairns is the most popular starting point for most Great Barrier Reef trips. There are plenty of dive shops here, and the prices are competitive.

But you really don’t need to spend much time in the city itself.

Book your flights so that you arrive the afternoon before your liveaboard departure. This will give you enough time to wander through town and explore the harbor. There’s actually not much more to see besides that!

If you have an extra day or two, rent a car and make your way to Port Douglas. Or even better, visit the Daintree Rainforest and Cape Tribulation.

The Daintree is the oldest rainforest in the world, and Cape Tribulation is the only place on earth where two natural wonders meet up. These are the Great Barrier Reef and the Daintree Rainforest.

giant clams under water
We saw so many giant clams like this one

You can’t fly for 24 hours after your last dive

Remember that if you’re diving the Great Barrier Reef, you can’t fly within 24 hours of your last dive. It’s best to pair your dive trip with one of the below local attractions.

  • Cairns and Port Douglas: Spend an extra two days exploring the lush walking tracks and epic swimming holes in the Daintree.
  • Townsville: After diving the SS Yongala wreck, visit nearby Magnetic Island. It’s a tropical island paradise with palm-fringed beaches and abundant wildlife.
  • Southern Great Barrier Reef: After spending time diving Lady Elliot Island, Lady Musgrave Island, or Heron Island, head to Fraser Island. It’s the largest sand island in the world with epic 4WD tracks.
Best time to go diving at Great Barrier Reef
Dive 5 of 11!

Is it worth diving the Great Barrier Reef?

Yes! The Great Barrier Reef is a world heritage site and a bucket list destination. There are so many incredible places to go diving along the reef, including Cod Hole, Ribbon Reef, and Osprey Reef.

And better yet, Northern Queensland has so much more to offer. Visit the Daintree Rainforest, go 4WD’ing on Fraser Island, live the island life of Magnetic Island, or go sailing through the Whitsundays.

What is the best time of year to dive the Great Barrier Reef?

The dry season from May to October offers the best conditions for diving the Great Barrier Reef.

Looking for the overall best months to plan your trip? September and October!

This is because you won’t have the trade winds during this time, the temperature starts heating up, and the days are sunny. And it’s just before the stinger season, so you won’t need to worry about that either.

diving swim throughs
The swim throughs at the Great Barrier Reef are awesome, and we were lucky enough to do a guided dive on this one

Where is the best diving on the Great Barrier Reef?

It depends on what you’re after. If you’re visiting the Great Barrier Reef for the first time, I’d recommend doing a scuba diving liveaboard from Cairns. After three days out at sea, spend another three days exploring the nearby Daintree Rainforest and Cape Tribulation.

But if you’re looking for the best diving on the Great Barrier Reef, the S.S. Yongala is an incredible wreck dive. You should have your advanced certification for this as you’ll be diving as deep as 30m, where the base of Yongala rests.

Great Barrier Reef Scuba diving liveaboard
Getting ready for the next dive

Are there Great White Sharks in the Great Barrier Reef?

It’s highly unlikely that you will find Great White Sharks in the Great Barrier Reef. This is because the water temperatures in north Queensland are too warm for them. They prefer temperatures between 12-24 degrees.

But there was a sighting of a Great White Shark on the southernmost part of the reef, near Lady Elliot Island. This was in 2020, but it’s only the second time one has been seen near the reef in 25 years.

How many days do you need in the Great Barrier Reef?

If you’re diving the Great Barrier Reef from Cairns, it’s best to do a 3-day liveaboard. This gives you more time in the water as there is so much to explore.


Are you planning your Great Barrier Reef scuba diving trip? Do you have any questions? Drop me a message in the comments section below.

Looking for more Australia travel inspiration? Check out my other posts!

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About Carryn

Hi, I'm Carryn.  I’m a South African trying to figure out my way through life by traveling and exploring. Join me as I share my travel stories and tips of life abroad.

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