K2 Climbing Season: Summit Window and Base Camp Traffic

The K2 climbing season runs from about late June to the end of August, and almost every summit happens in a short window in late July or early August. Summit numbers swing hard from year to year: well over 100 in 2023, about 41 or 42 in 2025, and none in 2026. If you are trekking to K2 base camp rather than climbing, the same months are your season, and they overlap with the busiest weeks of the expeditions.

K2 (8,611 metres) is on the border of Gilgit-Baltistan and China. It was first climbed on 31 July 1954, and first climbed in winter in January 2021. This guide explains the climbing calendar, the recent seasons, and how expedition traffic affects a visitor to Baltoro.

When is the K2 climbing season?

Climbers arrive at base camp in late June and early July, after a trek up the Baltoro Glacier from Askole that takes about a week. They spend weeks acclimatising and fixing ropes to the higher camps. Then they wait for the short spell of settled weather that decides everything.

Most summits fall from about 20 July to 10 August, and nearly always inside a few days. The Karakoram weather window is shorter and rougher than the Himalayan one. Snow that falls in July makes rope-fixing slow and avalanche risk high. Warm spells in August raise the rockfall danger between camps.

Winter attempts are a separate matter entirely and involve very few people. This guide is about the summer season.

How busy has K2 been?

The counts below come from the climbing chronicler Alan Arnette and from ExplorersWeb. The numbers are estimates and the sources differ slightly.

• 2022: a record year. About 150 people reached the top on a single day, 22 July, on fixed ropes.
• 2023: over 112 summits, most on 27 July.
• 2024: roughly 50 to 65, depending on the source. Several teams went together on the morning of 28 July.
• 2025: about 41 or 42 summits, all in August (11 and 12 August), later than usual. Two people died from rockfall between Advanced Base Camp and Camp 1, and some large teams gave up because of rockfall. Pakistan issued 555 climbing permits across its 8,000 m peaks that year, against 423 the year before.
• 2026: the quietest Karakoram season for about twenty years by permit numbers, with around 50 people attempting K2. Heavy July snow slowed rope-fixing, and wind held teams back. The main team, at Camp 3, turned round on 30 July when news came of the Broad Peak avalanche. No one summited K2.

What happened on Broad Peak in 2026?

On 30 July 2026 an avalanche swept ten climbers on Broad Peak at about 6,600 metres, between Camp 2 and Camp 3. All ten died, including the Nepali mountaineer Nirmal Purja. Broad Peak shares the upper Baltoro with K2, and its base camp is a short walk from K2's.

It shows how much heavy snow changes the year. Whatever the news of a good season, no summit season is safe.

Base camp traffic: what trekkers actually see

K2 base camp sits on the Godwin-Austen Glacier, reached from Concordia, the meeting of the Baltoro's ice streams. Concordia is where nearly all trekkers turn back, and beyond it is a rough stretch of glacier to the camp.

What you find there depends on the year. In a big year the camp is a small tented town of many teams, with cooks, porters and Pakistani high-altitude support. In 2026 it was much emptier. Trekkers walk through the same corridor, so expect other groups and porter lines on the Baltoro in July and August, whatever the summit count.

For trekkers the season is about mid-June to mid-September. July and August have the most stable weather but the most people. Our detailed pages cover that side: the K2 base camp trek, the best time for the trek and the Baltoro Glacier.

Who runs the expeditions, and how do you follow them?

Most commercial K2 teams are run by Nepali operators, with Pakistani guides and high-altitude porters alongside. In 2026 the operators named in season coverage were Seven Summits Treks, 14 Peaks and 8K Expeditions, plus Pakistani teams such as Summit Karakorum.

News from the mountain arrives slowly. Mobile signal at base camp is unreliable, teams depend on satellite devices, and military restrictions in the area limit what is reported. Season updates from Alan Arnette and ExplorersWeb are the usual sources, and they can lag the events by a day or two. For a visitor, that means a trekker at Concordia may know less about summit plans than someone reading online at home.

Permits and who can climb

Climbing K2 needs a permit through a registered Pakistani agency, and foreigners need trekking permits and a licensed guide for the Baltoro. Fees for international climbers have been raised in recent years and change; ask an agency for the current figure. For Pakistani trekkers the Baltoro is possible with a registered operator, but check the NOC position with the Gilgit-Baltistan tourism department before you book.

Getting to Skardu safely

Every K2 trip starts in Skardu. Flying from Islamabad avoids the road, which is worth knowing: the UK government advises against all travel on the Karakoram Highway between Mansehra and Chilas, and Skardu by road from Islamabad uses that stretch. Foreign-passport holders should check their own government's advice, since it can void insurance. Our Skardu page covers the town and access.

Is it worth visiting K2 in climbing season?

For most travellers, yes, provided you can commit two to three weeks and are fit. You see expeditions at work and the weather is at its best. If you want quieter trails, the shoulder weeks at either end of the trekking season are less crowded, though the weather is less settled.

The season does not suit anyone with limited time, health concerns at altitude, or a fixed date, since flights and weather in Skardu are unreliable. For a shorter view of the mountain, the K2 viewpoint and the mountain guide show alternatives. Our wider when to go guide helps with timing.

Frequently asked questions