The best time to visit Costa Rica: dry season or green season

Costa Rica is warm all year at low altitude, so the calendar is about rain rather than temperature, and about which side of the country you plan to spend time on. For the country overview, start with the Costa Rica travel guide; for arrival and the Central Valley, see San José.

Pacific beaches and the widest choice of parks: January to March. The Instituto Meteorologico Nacional (IMN) says the Pacific dry season runs from December to March, that April is a transition month, and that March is the driest and hottest month.

Green forests with fewer people: May, June and November. The rainy season is only getting started in May and June or winding down in November, and mornings are the time to be outdoors.

A beach week in the green season: July or August in Guanacaste. IMN describes a relative decrease in rain in July and August on the Pacific side, the veranillo, or little summer, when the trade winds strengthen.

The Caribbean coast: February to March, or September to October. The coastal zones have two relatively dry periods in those months.

Turtle nesting: July to October for green turtles at Tortuguero, March to June for leatherbacks, according to the Costa Rica Tourism Board.

The lowest prices: the green season. September and October have the least pressure on rooms and parks on the Pacific side, in exchange for the heaviest rain.

Avoid for road trips on the Pacific side: September and October. IMN lists them as the wettest months, and the UK government warns of flooding, landslides and road closures in the peak rainy period.

IMN divides the Pacific side into a well-defined dry season and a rainy season. The dry season runs from December to March, with April as a transition month, and the dry season starts first in the northwest and last in the southeast. The rainy season runs from May to October with November as a transition month. IMN adds that September and October are the wettest months, because of cyclonic systems, monsoon winds from the equatorial Pacific and sea breezes, and that rain falls mainly in the afternoon and early evening.

The Costa Rica Tourism Board frames the year as a dry season from December to April and a green season from May to November. That is a useful planning shorthand, as long as you keep in mind that April is a transition month and the exact timing shifts by region.

This grid gives the Pacific calendar from the national weather service and flags where the Caribbean differs.

Guanacaste in the northwest has a long dry period. IMN says the dry period in the northern Pacific region lasts from three to six months depending on the subregion, and the Guanacaste plain can have a severe climate with irregular rain. Expect the driest landscapes late in the dry season and greener hills once the rains settle in. It is the best choice for a beach trip in July or August, when the veranillo reduces rain.

Further south, the central Pacific around Quepos and Manuel Antonio National Park has what IMN calls a long and severe rainy period and a short, moderate dry period. The south, including the Osa Peninsula, has a short, favorable dry period and an intense rainy season. Wildlife is visible year-round, but in the rainy months the odds of a dry morning matter more than the date.

Hours and closing days can change, so check the SINAC page before you fix a day around them.

The Caribbean slope has no defined dry season. IMN says rain stays between 100 and 200 mm in the least rainy months, which is a considerable amount. The coastal zones have two relatively dry periods, from February to March and from September to October, and two rainy periods in between, the stronger one from November to January and another from May to August with a peak in July. December is the rainiest month, because of cold fronts from the Northern Hemisphere that are present between November and May and have their greatest effect from November to March. Rain falls mostly at night and in the morning.

That makes the Caribbean the counterweight to the Pacific. In September and October, when the Pacific is at its wettest, the Caribbean coast has a relatively dry spell. The Tourism Board says green turtles nest at Tortuguero mainly from July to October, leatherbacks from March to June, hawksbills from April to October and loggerheads from April to May. Use licensed local guides and follow the park rules for night visits.

The northern lowlands around Arenal Volcano National Park are in IMN's northern region, which belongs to the Caribbean rain regime. IMN describes rain throughout the year with a reduction in February, March and October. Plan for rain in any month, and treat a clear view of the summit as a bonus rather than a promise. Hot springs, hanging bridges and waterfall walks work in every season.

Monteverde and other cloud forests sit high enough to be cool and misty. IMN notes that fog is very frequent above about 1,600 meters. Bring a rain jacket and a warm layer whenever you go, and book the first guided walk of the day.

The UK government advises you to avoid volcanic areas during and immediately after heavy rainfall, when there is increased risk of lava flows, and to check news reports and local advice before traveling to any area around volcanoes. It also notes that there have recently been significant eruptions at Poás. Check park status before you build a plan around any volcano.

The Tourism Board recommends visiting national parks in the morning in the green season, and the IMN rain pattern explains why: afternoon and early evening is when the Pacific side gets its rain. Start early, plan indoor or rest time for the middle of the afternoon and keep the evening flexible.

Roads are the second constraint. The UK government says road conditions are generally good on main routes, but heavy rain in the rainy season can cause potholes and landslides that block roads. It also says the hurricane season usually runs from June to November and that the June to November period is the peak rainy season, with flooding and landslides causing road closures. Build slack into every driving day, avoid night driving on mountain roads and check the road before the last stretch to a lodge.

May and November are the best compromise. The rainy season is either only getting started or winding down, and demand is below the dry-season peak. You trade away the most reliable beach weather. December is the opposite: the dry season has begun and the forests are still green, but holiday demand is high.

April sits between the seasons. It is a transition month, so you can have dry mornings and the first afternoon storms in the same week. Book flexible accommodation and keep the best outdoor activity for the morning.

Avoid September and October on the Pacific side if you plan a long self-drive with remote lodges, unpaved final stretches or river crossings. Choose the Caribbean for those weeks instead.

Avoid the Christmas and New Year weeks and Holy Week if you want low prices and empty trails. These are the busiest weeks.

Avoid March and April in Guanacaste if you dislike dry heat and dusty landscapes. IMN calls March the driest and hottest month.

Avoid the Caribbean from November to January if your trip depends on dry weather. That is its main rainy period, and December is the rainiest month.

The Ministry of Labor lists Holy Thursday and Good Friday among the mandatory paid holidays, together with 1 January, 11 April, 1 May, 25 July, 15 August, 15 September and 25 December. Holy Week moves with Easter, so in 2027 Holy Thursday and Good Friday fall on 25 and 26 March. Many Costa Ricans travel to beaches during these days, and some businesses close, so book rooms, rental cars and tours early.

The UK government warns that rip currents are very common on any beach in Costa Rica and that there are often no lifeguards. Swim where locals swim, ask your hotel about the day's conditions and never swim alone.

Pack a light rain jacket, quick-drying clothes and shoes that handle mud in every season. Add insect repellent and sun protection for both coasts, and a warm layer for Monteverde and the volcano areas. A dry bag protects a phone and camera on boat trips and river crossings. For connectivity on remote roads, compare options in the eSIM guide, and for what to ask when choosing cover, see travel insurance. If you plan to combine buses with a rental car, read getting around.