Sudden stratospheric warmings (SSWs) are abrupt rises in the wintertime polar stratosphere that also affect the troposphere. Their study is hampered by the limited observations in the stratosphere and mostly relies on reanalyses, i.e., models that include observations. Here we compare the representation of SSWs by the most used reanalyses. SSW results are consistent across reanalyses but some differences are found, in particular before the satellite era.