In September 2026, experts in Haute-Savoie measured Mont Blanc and recorded an altitude of 4,807.47 meters. This figure represents the most recent official height for the mountain that is widely regarded as the highest summit in Western Europe.
Compared with the measurement taken in 2023, the summit is now 1.88 meters higher. The 2023 reading stood at 4,805.59 meters, which at the time was noted as a historic low for the peak.
Earlier surveys had shown a pattern of decreasing altitude, gradually reducing the recorded height to that 2023 minimum. The recent increase therefore marks a reversal of that earlier trend.
They share their findings every three years to build a dataset suitable for tracking long‑term variations.
Jean des Garets, president of the chamber of surveying experts of Haute-Savoie, reminded observers at a press briefing that "the summit is in perpetual movement," noting that the altitude had varied from 4,805 meters in 2023 to nearly 4,811 meters back in 2007.
The geometer experts of Haute-Savoie carry out yearly measurements of Mont Blanc’s height. They share their findings every three years to build a dataset suitable for tracking long‑term variations.
As part of their routine, the specialists also measure the calotte of snow and ice that covers the mountain’s rocky core, keeping tabs on how this layer changes over time.
During their observations, the experts highlighted that 2026 was a "particularly dry" year, a condition that influences the amount of snow and ice present on the summit.
They further recorded that the altitude at which the air temperature reaches zero degrees Celsius—the 0 °C isotherm—had exceeded 5,000 meters in 2026, indicating a shift in the thermal profile of the atmosphere above the massif.
Both the regular survey teams and the commentators attribute the continual fluctuations in Mont Blanc’s height to climate change, which affects both the ice cover and the high‑altitude temperature layers.
The reference to a near‑4,811‑meter reading in 2007 shows that the summit has previously reached greater heights, underscoring that the current value sits within a range of natural variability.
As of the September 2026 measurement, Mont Blanc’s altitude is fixed at 4,807.47 meters, reflecting the latest point in an ongoing series of rises and falls driven by environmental factors.