Steamboat Geyser is located in the Norris Geyser Basin of Yellowstone National Park. It is the world's tallest active geyser. Steamboat Geyser has two vents: a northern one and a southern one. These vents are about 20 feet (6.1 meters) apart. The northern vent produces the tallest water columns, while the southern vent's water columns are shorter.
Before 1904, Waimangu Geyser in New Zealand had eruptions that reached up to 1,600 feet (490 meters). However, in 1904, a landslide changed the water table, and the geyser has not erupted since. Excelsior Geyser in Yellowstone's Midway Geyser Basin and Semi-Centennial Geyser near Roaring Mountain on the Grand Loop Road were once reported to have eruptions as tall as Steamboat, reaching up to 300 feet (91 meters). Excelsior has not erupted since 1985 and now functions as a hot spring. Semi-Centennial had one eruption of this height in 1922 and has been dormant since.
Major eruptions of Steamboat Geyser usually last between 3 and 40 minutes. Some eruptions in 2018 lasted more than an hour. During these eruptions, water may be thrown more than 300 feet (91 meters) into the air. Steamboat does not erupt at regular times. The time between major eruptions has varied from three days to fifty years. The geyser was dormant from 1911 to 1961. In 1964, 29 eruptions were recorded, which was the highest number in a single year. In 2018, the geyser started a long period of frequent activity that continued through at least 2022. More than 40 eruptions were recorded each year in 2019 and 2020.
Minor eruptions of 10 to 15 feet (3.0 to 4.6 meters) occur much more frequently.
After an eruption, the geyser releases large amounts of steam for up to 48 hours. Sometimes, water may return to Steamboat during this time, causing it to jet water again, though to lesser heights. Cistern Spring, which is nearby, completely drains after a major eruption. It refills within a few days.
Recent eruptions and active phase of 2018–2025
The most recent eruption of Steamboat Geyser happened on February 27, 2026. This was the 173rd eruption since the geyser became active again in early 2018.
In 2019, the 48th eruption occurred on December 26. This set a new record for the most eruptions in a single calendar year. The calendar year 2020 also had 48 eruptions, which matched the record from 2019.
In 2018, Steamboat Geyser became more active. Between March 15, 2018, and May 7, 2023, there were 165 major eruptions. Specifically, 32 eruptions occurred in 2018, 48 in 2019, 48 in 2020, 20 in 2021, 11 in 2022, and 9 in 2023. This broke the record from 1964, which had 29 eruptions in a calendar year. The record from 2018 was broken on August 27, 2019, when the 33rd major eruption of that year happened.