Low tide and high tide in Zanzibar: what this means for swimming

In short

Off Zanzibar, low tide and high tide alternate twice a day. The moon phase determines how great the difference is: it is greatest at full moon and new moon, and smallest at half moon. On the east coast, the sea recedes over wide reef flats, often more than 1 km, in places up to 3 km. For your beach days this means: the right moment for swimming depends on the tide, and at low tide a walk out across the tidal flats is worth doing.

How the tides work in Zanzibar

The tides off Zanzibar are semi-diurnal: 2 high waters and 2 low waters per day. On average, around 12 hours 25 minutes pass from one high water to the next. This is a general astronomical value, not a fixed time for a particular beach. Low tide and high tide therefore shift from day to day.

How far the water rises and falls depends on the moon. At full moon and new moon, the sun and moon line up, their gravitational forces combine, and the difference between high water and low water is then at its greatest. This is called a spring tide. At half moon, the forces partly cancel each other out, and the difference is at its smallest. This is the neap tide. There are 2 spring tides and 2 neap tides per lunar month, as NOAA’s National Ocean Service explains.

In practical terms, this means: in the days around full moon and new moon, the sea goes out particularly far and comes back particularly high. Around half moon, the change is more moderate.

East coast: when the sea goes far out

The east coast of the main island of Unguja is characterised by a fringing reef, a reef that lies close inshore in shallow water. A study on coastal ecodynamics describes wide reef flats there that frequently extend more than 1 km, and in some sections up to 3 km, into the sea. Between the beach and the reef edge lies the lagoon, a shallow basin over sand and seagrass. At low tide, the flats and large parts of the lagoon fall dry.

For you this means: at low water, it is a long way to deep water. For swimming and snorkelling, high water is the better time. At low tide, the lagoon belongs to walkers and the seaweed farms.

At low water you see the seaweed farms as long rows of stakes and lines in the mudflats. According to a study by the Institute of Marine Sciences in Zanzibar, a large proportion of the farms studied lie right in the zone that falls completely dry at spring-tide low water. A nationwide census from 2011 put the number of people working in seaweed farming on Unguja at around 8,664. Work on the seaweed fields at low tide is part of everyday life on the east coast.

North and west

According to the same coastal study, the north-west coast of Unguja has narrower tidal zones than the east. The tidal flats are less extensive there, and deep water lies closer to the beach.

Nevertheless, the same applies to the north: there, too, mudflats fall dry. A study of the northern tip near Nungwi describes a tidal zone of around 2 km² with a fringing reef that falls dry at spring tide. At times, up to 150 collectors gather invertebrates there. The widespread assumption that in the north there is deep water right away at any state of the tide does not hold across the board.

The team in Arusha knows the tides in Zanzibar from first-hand experience. The north around Nungwi and the north-west around Kendwa are significantly less affected by the tides. In the east, where most beaches and tourist accommodation are located, and in the south, the sea recedes further for around six hours, in the team’s experience. Then you walk a few hundred metres to the water or out onto the mudflats. At high tide, swimming is possible as normal. When and how far the sea recedes on a given day is hard to predict. Let the team know during planning if being able to swim at any time of day is important to you.

Planning your beach days

Take the moon phase into account when planning. Around full moon and new moon the water recedes particularly far. Around half moon, more water remains in the lagoon. Which month you travel in also depends on the rainy season and the dry season. The overview of the best time to visit Tanzania helps you decide.

It is best to ask at your accommodation for the exact times each day. There is no official tide table for guests for Zanzibar: the British tide service EasyTide lists no station for the island, and the forecasts of the US agency NOAA do not apply to the Indian Ocean.

Make the most of low tide. A walk into the mudflats shows you the lagoon from the inside: seagrass meadows, tidal pools, seaweed fields. Ask at your accommodation beforehand when the water comes back.

Which beach suits you depends on your plans. Wildfinder’s Zanzibar page presents 4 beaches: Nungwi Beach is lively, with water sports and sunsets. Kendwa Beach is quieter and good for snorkelling and relaxing. Paje Beach is known for kitesurfing. Jambiani Beach is quiet, with swimming and local cuisine. The team in Arusha chooses the accommodation to suit your preferences, from a small boutique hotel to a resort on the beach.

Caution on the mudflats

Water shoes are a must on the mudflats; what else you pack is on the packing list for Tanzania. The shoes protect you from two typical hazards in shallow water.

According to the fish database FishBase, the stonefish also occurs off the coast of Tanzania. Its habitat is sandy or rubble-strewn reef platforms and shallow lagoons, especially at low water. Stepping on its spines is very painful.

The situation is similar with sea urchins. According to the Divers Alert Network (DAN), sea urchin injuries typically result from stepping on the spines in shallow water and in tidal pools. With sturdy shoes and an eye on the ground, you steer clear of both animals.

Correct as of October 2026

Frequently asked questions about the tides in Zanzibar