Where to Dive in September: 9 Best Destinations

Reef manta rays gliding over the coral reef near Dhigurah, South Ari Atoll, Maldives — Reef manta rays over the coral at South Ari Atoll, near Dhigurah — photo courtesy of Fari Dive Center.

The best places to dive in September are Komodo (the northern sites at the end of the dry season), Nusa Penida in Bali (mola mola and mantas), the Red Sea (hot, clear water), Koh Tao and the late-summer Mediterranean: Malta, Greece and Croatia. The Maldives and the Azores are also worth considering.

September is a good shoulder month. The Mediterranean is still warm but the summer crowds thin out, Indonesia is at the end of its dry season, and the Red Sea is at its hottest. In Southeast Asia, the Andaman Sea is still wet, and the main season there reopens in October. Use this guide to find places where September works well.

September Dive Destinations at a Glance

Destination	Why September	Water temp (°C)	Visibility	Level	Book
Komodo, Indonesia	End of the dry season; northern sites still at their best	24–28	15–30 m	Intermediate to advanced	Komodo diving, Komodo season guide
Bali and Nusa Penida, Indonesia	Mola mola season and reef mantas	21–27	15–30 m	Intermediate	Bali diving, Bali dive spots
Maldives	Southwest monsoon: quieter atolls, mantas, whale sharks	28–30	15–30 m	All levels; advanced for channels	Maldives diving, Dhigurah
Red Sea, Egypt	Hottest water of the year; reefs, wrecks and sharks	28–30	25–40 m	All levels	Sharm El Sheikh, Hurghada, Marsa Alam
Koh Tao, Thailand	Gulf of Thailand dives and Open Water courses	29–30	10–25 m	All levels; beginners	Koh Tao diving, Open Water course
Malta and Gozo	Late-summer sea still warm; fewer visitors	24–26	20–30 m	All levels	Malta diving, Malta dive spots
Greece	Warm sea and quieter islands after peak season	24–26	20–30 m	All levels	Greece diving, Crete
Croatia	Warm Adriatic with calmer crowds	22–24	15–25 m	All levels	Croatia dive spots
Azores, Portugal	Late-summer open-ocean diving	21–23	20–30 m	Intermediate	Azores dive spots

Water temperatures and visibility are typical ranges and vary by site and year.

Komodo in September

September is the end of the dry season, and the northern sites such as Castle Rock, Crystal Rock and Batu Bolong are still in their best period. The south of the park is colder because of upwellings from June to September. See the Komodo season guide and Komodo dive spots.

Diver swimming alongside a sea turtle over the reef in Komodo National Park, Indonesia — Diver and sea turtle in Komodo National Park — photo courtesy of Divers Paradise Komodo.

Bali and Nusa Penida in September

Mola mola season continues at Nusa Penida in September, and reef manta rays can be seen around the island throughout the year. Expect cooler water and some current, so a good wetsuit and some diving experience help. See the Bali dive spots.

Diver with a reef manta ray over the coral reef at Nusa Penida, Bali — Reef manta ray at Nusa Penida — photo courtesy of Pure Dive Resort Nusa Penida.

Maldives in September

The southwest monsoon is winding down, and the atolls are quieter than in the dry season. Manta rays gather in Baa Atoll around Hanifaru Bay from roughly June to October, and whale sharks can be seen in South Ari Atoll throughout the year. See the Maldives season guide and Dhigurah.

Red Sea in September

Water is at its warmest in September, around 28–30°C, so a thin wetsuit is enough. Visibility is generally excellent and the reefs and wrecks are diveable year-round. Liveaboards also run the southern and offshore routes. Read the Red Sea season guide.

Split-level shot of a shallow coral reef and the Sharm El Sheikh coastline, Red Sea — A shallow reef off Sharm El Sheikh — photo courtesy of Aqua Sharm Diving College.

Koh Tao in September

Koh Tao is on the Gulf of Thailand side, where diving continues all year. It is a popular place to learn to dive, with warm water and calm sites for beginners. See the Koh Tao dive spots.

Scuba diver swimming through a large school of fish near Koh Tao, Thailand — A diver moves through a school of fish off Koh Tao — photo courtesy of Chalok Reef Divers Koh Tao.

Malta and Gozo in September

September is one of the best months in Malta: the sea is still warm after the summer, and the crowds are thinner. Wrecks, caves and shore dives are all available, and beginners can start with an Open Water course in Malta.

Greece in September

The islands are quieter after August, but the sea is still warm. Crete, the Cyclades and the Ionian islands all have dive centers running boat dives and courses. See our Greece dive guide.

Croatia in September

The Adriatic is still warm in early September and crowds are lighter than in midsummer. It is a good month for wreck and wall dives. See the Croatia dive guide.

Azores in September

Late summer is still part of the main diving season in the Azores. Dive centers run open-ocean trips and dives on volcanic reefs, with clear water in settled weather. See the Azores dive guide.

Liveaboards in September

A September liveaboard works best in these regions:

Red Sea: hot, dry weather with north and south routes. Browse Red Sea liveaboards.
Komodo: the end of the dry season. Browse Komodo liveaboards.
Maldives: southwest monsoon trips with fewer visitors. Browse Maldives liveaboards.

Be Underwater is a marketplace: trip pages list dates, cabin availability and mandatory extras, and the operator runs the trip. Read the first liveaboard guide if this is your first one.

FAQ: Where to Dive in September

Where is the best diving in September?

Komodo, Nusa Penida, the Red Sea and the late-summer Mediterranean (Malta, Greece, Croatia) are the strongest choices in September.

Is September a good month for the Red Sea?

Yes. The water is at its warmest and visibility is generally excellent. It is hot above water, so plan around the midday heat.

Is September a good time to dive in Europe?

Yes. The Mediterranean is still warm and the crowds are thinner than in July and August.

Can I dive in Thailand in September?

Koh Tao, on the Gulf of Thailand side, is diveable all year. The Andaman Sea side is in its wetter season, and the high season there reopens in October.

Can beginners dive in September?

Yes. Koh Tao, Malta, Greece and the Red Sea have beginner-friendly sites and instructors. Komodo and Nusa Penida have stronger currents and suit divers with some experience.