Phong Nha cave closures and tours 2026: a month-by-month calendar

Phong Nha 2026 at a glance: weather, crowds, and cave access

The best time to book adventure caves in Phong Nha is February to April, when temperatures sit at 22 to 30°C and Son Doong, Hang En, and Tu Lan run at full access. That window also carries peak prices and the year's biggest domestic crowd spike around Tet on 17 February 2026.

Adventure caves need licensed operator permits. Son Doong runs only through Oxalis, and you should confirm the 2026 dates on Oxalis before building a trip around them. Son Doong normally takes bookings 6 to 12 months ahead; Hang En and Tu Lan often reopen in mid-January after the wet season, but verify those dates with the operator. Expect to pay about US$3,000 for Son Doong, about US$400 to 500 for Hang En, and about US$300 to 600 for Tu Lan. Guided options include Oxalis, Jungle Boss, and Phong Nha Discovery.

January is cooler and drizzly at 16 to 22°C, with low domestic travel. May to August is hot and dry at 28 to 36°C: caves run, but midday heat and afternoon storms can disrupt plans, and domestic summer crowds arrive June to August. Son Doong's season typically ends in mid-August.

From September to November, Phong Nha is wettest at 24 to 30°C. Phong Nha Cave boat tours can close for flooding. Operators suspend Tu Lan, Hang Va, Nuoc Nut, and Son Doong. Dark Cave's zip line and mud section may close, and roads to the Botanic Garden can flood. December cools to 18 to 24°C, with some tours resuming late in the month and limited availability around Christmas and New Year.

Free or self-guided options follow a different calendar: Paradise Cave, Phong Nha Cave by boat, Dark Cave, and the Botanic Garden stay open more often, though wet-season closures still hit. Paradise Cave entry is about 250,000 VND. A Phong Nha Cave boat tour costs about 150,000 VND plus the boat fee. Hours and prices change, so confirm on the official website before travelling.

## January and February in Phong Nha: cool starts and Tet closures

January is the coolest and quietest stretch of the year in Phong Nha, with temperatures of 16 to 22°C and regular drizzle. The adventure caves that anchor the high season, Son Doong, Hang En and Tu Lan, usually reopen in mid-January, and Oxalis Adventure is the only operator licensed to run Son Doong. Confirm Oxalis 2026 dates before you book flights, and check Hang En and Tu Lan start dates with whichever operator you book. Arrive in the first half of the month and you may find the caves still shut.

Tet falls on 17 February 2026, and the holiday reorganises the second month. Domestic travel surges, some operators shut down around the holiday, and buses, trains and rooms fill with Vietnamese families travelling on their own break. Book transport and accommodation before Tet week rather than during it, and expect operator shutdowns on and around 17 February.

When the adventure caves are closed, the park still has options that need no permit. Paradise Cave charges about 250,000 VND entry, the Phong Nha Cave boat tour costs about 150,000 VND plus the boat fee, and Dark Cave and the Botanic Garden are self-guided. These are the practical fallback for a January arrival that lands before the Son Doong, Hang En and Tu Lan season restarts.

Booking lead times are the other early-year trap. Hang En and Tu Lan need 1 to 3 months ahead, while Son Doong needs 6 to 12 months ahead because departures are limited. Son Doong costs about US$3,000, Hang En about US$400 to 500, and Tu Lan about US$300 to 600. The park can close caves at short notice, so check the operator's own 2026 calendar before you pay.

From February to April, Phong Nha temperatures sit at 22 to 30°C, and rain is less likely than from September to November. March and April are the most reliable months for cave tours because the dry season keeps river levels and trails predictable. All adventure caves on the permit list can run: Son Doong, Hang En, Tu Lan, Hang Va, Nuoc Nut, and Over Cave. The self-guided and free sites also operate normally, including Paradise Cave, Phong Nha Cave by boat, Dark Cave, and the Botanic Garden.

Prices peak in this window. Son Doong costs about US$3,000; Hang En about US$400 to 500; Tu Lan about US$300 to 600. Permits are required for all adventure caves, and only Oxalis runs Son Doong. Book Son Doong 6 to 12 months ahead. Book Hang En or Tu Lan 1 to 3 months ahead. Hang Va, Nuoc Nut, and Over Cave also require licensed operator permits; prices vary by operator and departure date.

For the non-permit caves, Paradise Cave entry is about 250,000 VND. The Phong Nha Cave boat tour is about 150,000 VND plus the boat fee. Tet 2026 falls on 17 February, which causes domestic crowds and operator shutdowns, but by March and April the holiday traffic has cleared and schedules are back to normal. Morning starts are better for the boat tour and for the walk into Paradise Cave, before midday heat builds. Afternoon storms are possible but rare compared with May to August.

Licensed operators include Oxalis, Jungle Boss, and Phong Nha Discovery. Briefings cover flash floods, slippery trails, and leeches in wet season; in March and April flash flood risk is lower, but the park can still close caves at short notice. Confirm exact 2026 dates and prices with your operator, because closure dates and flood season timing shift. If your dates are fixed, book the permit first, then arrange a Phong Nha farmstay or a local stay around the tour departure.

Phong Nha reaches 28 to 36°C from May to August, and the heat peaks between 11am and 3pm. Afternoon storms are common, so the shape of a summer day here is an early start on the trail and the middle of the day spent underground, where cave temperatures sit far below the surface reading. The caves stay open through this stretch.

Son Doong is the exception. The overnight expedition season typically ends in mid-August, and Oxalis Adventure is the only operator licensed to run it, so book 6 to 12 months ahead for any departure before that cutoff. Hang En and Tu Lan need 1 to 3 months of lead time, and Jungle Boss and Phong Nha Discovery also run guided trips in the park. Permits are required for all adventure caves, including Son Doong, Hang En, Tu Lan, Hang Va, Nuoc Nut and Over Cave. You cannot walk into any of them alone.

Domestic summer crowds rise from June to August, when Vietnamese school holidays fill Phong Nha town and the boat docks. Paradise Cave, about 250,000 VND, and the Phong Nha Cave boat tour, about 150,000 VND plus the boat fee, take most of that traffic, so plan for first thing in the morning or late afternoon. Rain falls hard and briefly, trails get slick, and leeches appear on wet ground; long socks and closed shoes help on the Tu Lan and Hang Va approaches. Flash floods are a real risk in the valleys. Rangers and operators brief groups each morning, and itineraries change at short notice.

Prices are highest in the February to April window, but summer demand still means booking early secures a date. If your plans sit near mid-August, confirm with the operator before you book flights around Son Doong. The season can close earlier depending on rainfall, and park staff can suspend caves at short notice.

## September to November: Phong Nha flood season and cave suspensions

From September to November, Phong Nha weather runs 24 to 30°C, and this is the wettest period of the year. Rain suspends the adventure caves and can close the Phong Nha Cave boat tour, so the season rewards travelers who can reroute rather than those locked to a fixed itinerary.

The park suspends Tu Lan, Hang Va, Nuoc Nut, and Son Doong for the season. All four require permits from a licensed operator, and Son Doong runs only through Oxalis. Booking leads of 6 to 12 months for Son Doong do not help in this window because the caves are not taking groups, and the dry-season price of about US$3,000 is moot until they reopen. Tu Lan, normally about US$300 to 600, sits in the same suspended list.

Even the standard tours are unreliable. Phong Nha Cave boat tours can close because of flooding, and Dark Cave's zipline and mud sections may close on the same days. Roads to the Botanic Garden can flood, so check local conditions with an operator before setting out.

Self-guided options are Paradise Cave, Phong Nha Cave by boat, Dark Cave, and the Botanic Garden, and the wet season narrows that list. Paradise Cave entry is about 250,000 VND and the Phong Nha Cave boat tour is about 150,000 VND plus the boat fee, but confirm the river status before you pay, because the boat tour is the one that floods out.

Flash floods, slippery trails, and leeches are part of the wet season, so follow ranger and operator briefings rather than a printed schedule. The park can close caves at short notice, and exact 2026 closure dates and prices vary by operator. Ask Oxalis, Jungle Boss, or Phong Nha Discovery what is running before booking transport to Phong Nha. December brings cooler weather at 18 to 24°C, and some tours resume late in the month, so a trip in early December still needs a same-week check.

December brings cooler weather to Phong Nha, with temperatures of 18 to 24°C. Some tours resume late in the month and into January, but availability around Christmas and New Year is limited. Check with Oxalis, Jungle Boss, or Phong Nha Discovery before you plan around a specific departure.

Paradise Cave, Phong Nha Cave by boat, Dark Cave, and the Botanic Garden are the non-permit options. Paradise Cave entry is about 250,000 VND, and the Phong Nha Cave boat tour is about 150,000 VND plus the boat fee. Confirm hours and river conditions before you travel.

Six caves in Phong Nha-Ke Bang National Park run on permits from licensed operators: Son Doong, Hang En, Tu Lan, Hang Va, Nuoc Nut, and Over Cave. Son Doong is only through Oxalis. Hang En and Tu Lan book through operators such as Oxalis, Jungle Boss, and Phong Nha Discovery. You cannot buy these at the gate. You reserve a departure date, and the operator handles the permit and the park ranger.

Everything else is self-guided or boat-based. Paradise Cave entry costs about 250,000 VND and you walk the boardwalk on your own. Phong Nha Cave is a boat tour at about 150,000 VND plus the boat fee. Dark Cave and the Botanic Garden need no permit either. Hours and prices change, so confirm on the official website before you go.

Book Son Doong 6 to 12 months ahead. It costs about US$3,000, and February to April dates sell out first. Hang En costs about US$400 to 500 and Tu Lan about US$300 to 600, with 1 to 3 months of lead time. Verify 2026 prices with your operator, since rates move and closure dates differ between companies.

Safety comes down to the briefing. Flash floods close cave entrances and river sections, trails turn slippery, and wet-season leeches are common on Tu Lan and Hang Va routes. Ziplines and the mud section at Dark Cave cause injuries when people ignore harness instructions. Rangers and operators can cancel or reroute a trip, and the park may close caves at short notice. Most travelers stay in Phong Nha town or at a Phong Nha farmstay, so confirm your pickup time with the operator the day before.