When to Visit Cartagena: The Sky or the Sea, Pick Your Risk

Short answer: late January to early March if the old town is the point of the trip, September or October if the sea is. Cartagena’s temperature barely moves all year. What moves is the rain and, separately from the rain, the sea — and they do not move together. The dry months are the windy ones: blue sky, choppy crossing, island days quietly cut short. The wet months are the calm ones: afternoon downpours, flat water, lower prices.

Which means the boat matters more than the month. If you are coming between December and April and an island day is on the list, the Rosario Islands catamaran with lunch and snorkelling crosses the swell flat where a speedboat slams through it — €106 per person, 4.5 stars from 2,758 reviews on GetYourGuide. The rest of this page is why.

Ask when to come to Cartagena and you will be told December to April, dry season, done. That answer is half right and it hides the part that actually affects your holiday.

Here is the thing nobody leads with: the temperature does not change. The monthly average high runs between 31.1 °C and 32.3 °C — a spread of 1.2 degrees across the whole year — and the monthly mean low never drops below 24 °C. Humidity hovers around 80 per cent in every month. There is no cool season to aim for and no hot season to avoid.

The rainfall figures, which are more extreme than they sound

Cartagena collects about 1,074 mm of rain a year. January to April together account for roughly two per cent of it. October alone accounts for more than a fifth.

This is not a wet season and a dry season in the European sense. It is four months in which it essentially does not rain, followed by seven in which it genuinely does, with December as the hinge.

The catch in the dry season: it is also the windy one

The months with no rain are the months with the north-easterly trade winds, strongest from January through March. They are the reason a February afternoon in the old town feels bearable. They are also the reason your island trip may not go the way the booking page describes.

Colombia’s maritime authority, Dimar, regulates departures from Muelle de la Bodeguita according to sea conditions, and does so through the trade-wind season from roughly December to April. When it issues a warning for strong winds and dangerous swell, departures are suspended — and short of that, what happens far more often is quieter: operators bring the return time forward, because the sea builds through the afternoon.

So a perfect blue February day can still mean a shortened island day, a bumpy crossing, or a beach at Playa Blanca that is neither flat nor turquoise, because it faces open Caribbean.

None of this makes February a bad month. It makes it a month with a different risk profile than the one the brochure implies — and it is the reason which boat you choose matters more between January and March than at any other time of year.

The months nobody recommends, and what they actually offer

October is the wettest month on the chart and September the third wettest — and both bring the calmest water of the year. The trade winds have gone. Prices drop. The old town is walkable at a normal pace.

The rain in these months is not a British drizzle that sets in for the day; the annual total arrives in a small number of hours across a lot of afternoons. If your plan is an island day or an evening on the water, the sea is on your side in October in a way it simply is not in February.

The honest trade is this: in the dry months the sky cooperates and the sea does not. In the wet months the sea cooperates and the sky does not. Decide which one your trip depends on.

Four days on the water, and the months that suit each

The second of those is a speedboat day and the third is too; both feel the trade winds. The catamaran is the one that does not, and the sunset cruise sidesteps the question altogether by staying with the city skyline for two hours in the evening.

Then there is the crowd, which is a separate calendar again

Cartagena’s high season is short, specific and expensive:

• 19 December to 19 January is the official high season. 20 December to 2 January is the most expensive and most crowded stretch of the entire year, and hotels in the walled city are booked months out.
• Semana Santa — Holy Week, March or April depending on the year — is the only period comparable to it.
• Mid-June to mid-August is the Colombian school holiday, busy with domestic travellers rather than foreign ones.
• The Hay Festival takes over the old town for four days at the end of January; the 2027 edition runs 28 to 31 January. Rooms tighten and rates rise for that week.
• 11 November is the Fiestas de Independencia, Cartagena’s own independence celebration, with parades and street events across several days. It falls in the second-wettest month of the year, which tells you something about how much the rain really interrupts life here.

Put the two calendars together and the interesting gap appears: late January to early March, after the Christmas peak has cleared and before Semana Santa. Dry, reliably sunny, windy at sea, and materially cheaper than the four weeks before it.

What we would actually book, by month

January to March. The classic choice and still the right one if the old town, the walls and the castle and eating outdoors are the point of the trip. Put the island day early in the holiday so there is a spare day if the sea is against you.

April. Rain begins, wind drops, crowds thin. Probably the best single compromise month in the year.

May to August. Hot, humid, rainy in the afternoons, calm at sea. July and August bring Colombian holidaymakers. Good for boats, less good for long days on foot.

September and October. Very wet — October is the wettest month of the year — and in exchange the calmest at sea. Best water conditions, lowest prices, and the highest chance a given afternoon gets rained on.

November. Still very wet, but it carries the independence festival, which is the most Cartagenero thing on the calendar and not a tourist product.

December. The rain stops abruptly — 44.7 mm against November’s 178.3 — and the prices start. The first half of the month is one of the best-value windows of the year. The second half is the most expensive.

One thing that is true in every month

Whatever you book, book the outdoor part of the day for the morning. That is not about the season; it is about 31 degrees and 80 per cent humidity being the constant here, not the variable. The same logic runs through everything we say about visiting with children, and it applies just as well to adults who would simply rather not queue for a castle at two in the afternoon.

Our recommendation

For most people: come between late January and early March, and spend the island day on the catamaran. That window is dry, reliably sunny, past the Christmas peak and ahead of Semana Santa. It is also the windiest stretch of the year at sea, which is precisely why the slower, flatter boat is worth its €102 — two anchorages instead of five stops, and a crossing you are not braced against.

See dates and prices for the Rosario Islands catamaran

Travelling September to November? Take the speedboat and keep the money. The trade winds are gone and the water is flat, so the hull stops mattering. The Rosario Islands excursion with snorkelling and Playa Blanca rates 4.8 from 1,373 reviews — the highest rating of the four here — and costs €70.67 against the catamaran’s €106.

Check availability for the Rosario Islands excursion with snorkelling

First trip, and you want to see as much as possible? The five-stop tour with lunch and beach clubs has 6,635 reviews, more than any other activity in Cartagena, and costs €65.30. Be clear about what it is: five stops inside six and a half to seven hours, roughly two of which are spent travelling. If your idea of an island day is a hammock and a book, this is the wrong booking, and so is any of the multi-stop formats.

See dates and prices for the five-stop Rosario Islands tour

One free evening, or a group that does not fancy seven hours at sea? The two-hour sunset cruise costs €36, holds 4.7 stars from 1,270 reviews and asks for an evening rather than a day. It is also the honest fallback for a January trip where the forecast turns: an evening on the bay is far less exposed to the trade winds than a crossing to the archipelago.

Check times for the two-hour sunset cruise

Whichever month you land in, book the island day for the first half of your stay rather than the last. Between January and March that spare day is the difference between a shortened crossing and no crossing at all.