Bida Nok Diving Guide: Depth, Level, Trips (Phi Phi)

Featured image: Morningdew, CC BY-SA 3.0, via Wikimedia Commons.

Bida Nok at a glance

Bida Nok is one of two southern islets, alongside Bida Nai. Neither has landing access, so every visit is a dive or snorkel from a moored boat. Dive-guide listings place Bida Nok at 7.65500, 98.76681. Reported maximum depth varies by source: 25 m (82 ft) on PADI's dive site card, 30 m (98 ft) on a Phuket operator's page, and a wall to about 40 m (130 ft) on a Krabi operator's. A dive site has no opening hours. Your boat crew sets the dive times, and the tide and current shape the order of sites.

• Location: about 1.5 km (0.9 mi) south of Phi Phi Leh
• Entry: boat only, no beach or landing
• Depth: shallow sand in the east bay, wall to 25-40 m (82-130 ft) depending on source
• Current: weak to moderate, with drift possible on the south wall
• Reported visibility: about 15 m (49 ft)
• Best fit: new divers in the east bay, Open Water and Advanced divers on the wall

What you'll see underwater

Each side of the islet feels like a different dive. The east bay is a flat, sandy area ringed by staghorn coral, with boulders further out. Guides use it for first dives because it is shallow and calm. Past the boulders the bottom drops into a wall on the south side. Current can run here, which turns the dive into a drift. One Phuket operator suggests moving off the wall toward the big boulders and hovering near 18 m (60 ft). Reported sightings there include king mackerel, tuna and trevally. The north side tops out around 20 m (66 ft) before the reef falls away to sand. Guides report the most leopard shark sightings on this side, plus blue-spotted stingrays, cuttlefish and squid. Common finds elsewhere on the site include blacktip reef sharks, hawksbill turtles, morays, lionfish and schools of yellow snapper. A overhang with large gorgonian sea fans sits toward the end of the circuit. Whale sharks and mantas appear in operator write-ups as a possibility only. Treat them as luck, never as a reason to book.

Is Bida Nok right for your level?

Published levels disagree because the islet contains several dives. One operator rates it from absolute beginner upward, another calls it intermediate, and a third says all levels. All three are right for different sides. Depth, current and your guide's plan decide the answer on the day. Newly certified divers should ask for the east bay or the shallower north side. Advanced divers can ask for the south wall. Ask which side your boat will use before you pay. First-timers can read our discover scuba guide before choosing a trip.

Bida Nok vs Bida Nai vs Hin Bida and nearby sites

Do not confuse Bida Nok with Hin Bida. Hin Bida is a separate submerged pinnacle, also called Shark Point by one Koh Lanta operator. That operator lists it at roughly 1-20 m (3-66 ft) with mild to medium current. Bida Nai is Bida Nok's sister islet, and operators often pair the two in one trip. For depth and character at other sites, read our Hin Klang guide. Wall divers should compare it with the Palong Wall profile. Our full Phi Phi site list covers the rest.

How to get there and what a trip looks like

From Ton Sai Bay, you board a dive boat that motors south past Phi Phi Leh. Because there is no landing, the boat anchors or drifts while you dive. Day trips also leave from Phuket, Krabi and Ao Nang, and from Koh Lanta. Raya Divers, based near Ao Nang in Krabi, runs a Bida Islands day on Thursdays. One Koh Lanta shop sends boats to Koh Bida and Phi Phi on Monday, Wednesday and Saturday during its mid-October to mid-May season. Those trips typically leave at 8 or 9 am, run two dives and return by 2 pm. Boat times from each port vary with sea state, so ask your operator for the exact transit. Staying on Phi Phi shortens the day and gives you the most say over timing.

Costs and fees

A Bida Nok dive is usually priced as a two-dive day trip, and many shops add gear and lunch. Marine park entry is a separate line. One Koh Lanta operator lists the Phi Phi marine park diving fee at ฿240 for Thai nationals and ฿600 for foreign visitors per day, charged on top of the trip price (fees checked November 2026). Park rules and fees sit with the Department of National Parks, so check there for current amounts. Bida Nok trip prices vary by operator, boat size and departure port. Our Phi Phi diving price guide breaks down day trips, course dives and liveaboards.

When to go

One Phuket operator calls Bida Nok an all-year site. Another runs its Koh Lanta Bida trips only from mid-October to mid-May. Rough seas and low visibility are the usual reasons a boat skips a site. Reported visibility is about 15 m (49 ft), which is a typical figure, not a promise. Current rises around full and new moon on nearby pinnacles, so ask your guide about tide timing. Our Phi Phi diving season guide compares months. Water warmth is covered in our water temperature guide. For weather outlooks, see the Thai Meteorological Department.

Choosing an operator and diving responsibly

Pick a shop that briefs the site clearly and caps group size. Ask which side of Bida Nok you will dive. Ask the maximum depth, how current is handled and what the surface interval looks like. Compare shops in our Phi Phi dive shop guide. Training options are in our PADI course guide. Dive inside your certification and follow your guide's briefing. Protect the reef with good buoyancy, no touching and reef-safe sunscreen. Insurance matters for boat-only sites, so read Divers Alert Network guidance before you travel.

Snorkeling, courses and non-divers

Bida Nok has no beach, so snorkelers must swim from the boat. Ask your operator whether the east bay or a Bida Islands stop is included on snorkel days. Open Water students can use the shallow east bay for training dives. Non-divers can ride along on some trips, but check boat space and the planned stops first. Guides with shallow-water experience will know how the tide changes the bay.

Mistakes to avoid and who should skip it

Skip Bida Nok if you want guaranteed big animals or wreck diving. Sightings here are strong on reef life and leopard sharks, not certainty. Avoid these common planning errors.

• Booking Hin Bida and assuming it is Bida Nok
• Treating the deepest reported figure as your limit
• Assuming the trip price includes the marine park fee
• Expecting a landing or beach stop
• Skipping the question about which side the boat will dive