Andaman — December 2026 Fishing Report
December on the Andaman is the season at its apex. The northeast monsoon has settled into the established, predictable pattern that delivers the Andaman's finest weather, sea state, and fishing conditions. The Similan Islands liveaboard calendar is running at maximum capacity — every quality vessel is scheduled through Christmas and New Year with the international visitors who have timed their Thailand trip around the dry season's premier fishing window. The granite pinnacles are in full production: GT are active on the surface through extended dawn and dusk windows, wahoo are trollable across the offshore bank edges, and the dogtooth tuna at the Surin Islands' deep structures are jiggable in 25-metre visibility water. The Andaman in December offers no compromise and no asterisks. It is the complete fishing experience.
Water and Weather
December at the Andaman coast is defined by the northeast monsoon's full seasonal expression. Wind from the northeast at 8–15 knots is the consistent baseline; it creates mild 0.5–1.5 metre swell that the liveaboard fleet navigates comfortably in all directions. The western leeward sides of the Similan Islands are effectively glassy on most December mornings — the liveaboard vessels anchor stern-on to the granite boulders and the anglers have a perfectly stable casting platform for dawn surface sessions.
Sea surface temperatures have cooled further to 27–28°C — the annual minimum in the Andaman's offshore zone. This temperature range is optimal for the offshore pelagics that define the Andaman fishing calendar. Visibility at offshore sites is at the year's best: 25–35 metres at the Similan and Surin Islands, enabling precise visual fishing at depth and superb photographic conditions on the surface.
Phuket, Khao Lak, and the Andaman coastal provinces receive virtually no rainfall in December — less than 10mm typically. The days are consistently clear with brilliant blue skies. The Andaman coast in December is internationally recognised as one of the world's finest tropical marine environments.
What's Biting Now
Giant trevally — December GT fishing on the Similan granite pinnacles is as good as anywhere in Southeast Asia. The dawn surface window — 5:30 to 8:30 am — produces aggressive takes from resident GT in the 10–30kg range on large poppers and high-speed stickbaits. The dusk window, typically 4:30 to 6 pm, produces a second surface feeding opportunity. The combination of these two daily windows, across four or five days of a liveaboard itinerary, produces GT encounters that are the defining memory of any Similan fishing trip.
Wahoo — December is the Andaman's best wahoo month. These high-speed, razor-toothed pelagics concentrate on the offshore bank edges and the current lines between island structures in December's organised sea state. High-speed trolling at 14–18 knots with skirted lures and rigged mackerel; also targetable on fast-retrieved jigs in the 100–150m depth range over deep pinnacle bases. Wahoo from 10–30kg; fights brief but explosive.
Dogtooth tuna — Richelieu Rock and the deep Surin Island walls hold dogtooth tuna at their December best. The clear water and cooler temperatures activate the deep-feeding behaviour that makes these fish catchable on heavy flutter and slow-pitch jigs. Fish from 15–50kg; the dogtooth tuna's power at depth tests even experienced anglers on PE4-6 gear.
Spanish mackerel — Absolutely abundant across the entire Andaman fishing zone in December. Available to both liveaboard anglers (as a fill-in species between pinnacle drifts) and day-charter anglers from Phuket and Khao Lak. Chrome lure trolling and high-speed jig retrieves equally effective. An excellent species for newcomers to Andaman fishing.
Yellowfin tuna — Increasingly present on the December offshore grounds. Trolling offshore between the island chains and targeting feeding bird aggregations produces tuna encounters. Some December days at the Similan offshore produce mixed-bag trolling sessions with wahoo, yellowfin, and Spanish mackerel in the same day.
Grouper — Deep bottom fishing at the Similan and Surin reef bases produces December's best grouper catches — the cool, clear water brings these bottom dwellers out of their deep refuge onto the upper reef structures where live-bait and large-lure presentations can reach them.
What to Target This Month
Top pick: Similan Islands liveaboard Christmas or New Year week. The Christmas and New Year liveaboard departures to the Similan Islands combine the year's best fishing conditions with the world's most extraordinary tropical backdrop. A 5-night departure covering the Christmas week (arriving back on 26 or 27 December) or the New Year week (returning around 3 January) is the Andaman's most sought-after fishing booking of the entire year. The fishing quality — GT at dawn, wahoo trolling midday, beer and dinner watching the stars — is matched only by the experience of being on the water over the holiday period.
Second pick: Surin Islands / Richelieu Rock for dogtooth tuna. For anglers who have already experienced the Similan program and want the Andaman's next challenge, the Surin Islands liveaboard focuses on the deep-structure fishing that produces dogtooth tuna. December's clear water makes the Surin jigging program as technically demanding and physically rewarding as it gets. A Surin liveaboard can be combined with a Similan crossing for anglers with a 7-night itinerary.
Third pick: Khao Lak day charter for GT and mackerel. For land-based anglers, Khao Lak's day charter fleet provides December fishing from well-equipped vessels to the productive mid-channel grounds between the coast and the Similan chain. Full-day trips departing at 6 am targeting Spanish mackerel trolling, reef jigging for GT and barracuda, and anchored bottom fishing for grouper provide a genuinely satisfying December day without the liveaboard commitment.
What to Avoid
Avoid booking Christmas week liveaboard trips without 3-month advance notice — these are sold out by September in normal years. Avoid the Andaman west-coast beaches for shore fishing in December; the northeast monsoon creates onshore wind conditions on the eastern Gulf-facing shores but the Andaman's west-coast beaches remain pleasant beach environments rather than productive shore-fishing locations. Avoid attempting to extend late-December liveaboard programs into January without confirming marine park access — the Similan Islands park sometimes imposes brief New Year closures around public holiday periods; confirm current-year status with your operator.
December's Offshore Wahoo Window
Experienced Andaman liveaboard captains time their inter-island transits strategically in December to maximize wahoo opportunity. The 45-minute run between pinnacle stops, which might otherwise be dead time, becomes a productive trolling pass when rigged wahoo lures are deployed behind the vessel at full passage speed. The deep offshore water between the Similan chain's northern islands produces regular wahoo strikes during these transit trolling runs. A boat that catches one GT at dawn and one wahoo during the midday transit and repeats this across five days has produced 10 trophy encounters in a single liveaboard trip — a result that would be exceptional from most fishing destinations in the world.
Venue Spotlight
Similan Islands (Mu Ko Similan National Marine Park) — The nine-island Similan chain at December peak is the Andaman's absolute highlight. The liveaboard programs running from Khao Lak's Tab Lamu Pier include dedicated fishing programs with experienced crews who understand the dawn GT windows, the mid-channel wahoo trolling routes, and the deep jigging spots that produce dogtooth encounters. Multiple operators offer Christmas and New Year special programs — these fill months ahead of departure. Verify the marine park's current entry regulations and park fees with your operator.
Surin Islands and Richelieu Rock — The northern Andaman's specialist destination is reached via liveaboard from Kuraburi Pier. December's calm sea state makes the passage to the more exposed Surin chain comfortable, and Richelieu Rock — the celebrated limestone pinnacle — is at its most productive in December when the water clarity enables precise deep jigging. The combined Similan-Surin itinerary, running 7 nights, is the most comprehensive Andaman fishing program available.
Phuket (Ao Chalong and Cape Panwa) — For the land-based Phuket visitor, the charter operations from Ao Chalong Bay run full-day December programs to the offshore reef systems 15–30km from the island. Spanish mackerel, reef GT, and large barracuda are the consistent targets. The December weather makes these day trips comfortable and reliable. Phuket's full international resort infrastructure — available at peak-season rates from late December — makes this the most accommodation-comfortable Andaman fishing base.
Logistics in December
Phuket International Airport is the Andaman gateway, with the Christmas-New Year holiday season bringing its highest passenger volumes of the year — book flights and check in early. Khao Lak accommodation books out completely for liveaboard departure dates in the Christmas period; confirm accommodation before booking the liveaboard. Krabi Airport provides an alternative Andaman entry point for Krabi-based fishing programs. Andaman accommodation rates in December are at their annual maximum — budget for December peak rates across all accommodation categories. The investment in a December Andaman liveaboard fishing trip represents the highest cost-per-day fishing program available in Thailand; it also delivers the highest quality.
Looking Ahead to January
January continues the Andaman peak season in full operation. Sea conditions remain calm, the GT fishing on the Similan pinnacles maintains December quality, and the liveaboard program continues without reduction. January is arguably the most reliably productive month of the entire Andaman season — the Christmas crowds have departed and the boats run quieter schedules in the best of the year's remaining weather. January Andaman trips, booked now, represent excellent value in a remarkable fishing destination.
