Records taken from Russia’s statistics agency put war deaths at between 390,000 and 450,000, depending on how they are counted. Experts say the true figure is probably higher still.
More than 400,000 Russians have been killed fighting in Ukraine since Moscow launched its full-scale invasion in February 2022, according to data leaked from the country’s state statistics agency.
The data, taken from Rosstat by two hacking groups, includes more than 11 million death certificates recording each person’s age, place of residence and where they died.
An analysis by the Guardian, one of a small group of media outlets given access to the data, found 412,576 certificates that explicitly linked deaths to the war, either through official cause-of-death codes or written references to combat.
Russia has not published official figures on its military losses since September 2022 and treats them as a state secret.
The breach was carried out by the Cyber Partisans, an opposition-linked Belarusian hacking group, and Silent Crow, a Ukrainian hacking collective. They announced it on 1 November and released the data over the weekend, saying they had taken about 23 terabytes of internal documents and statistics.
Rosstat confirmed it had been hacked but denied that any sensitive information had been obtained.
The figures have not been fully verified. Two independent Russian news outlets, Meduza and Mediazona, say they are checking the data, including whether any of it has been falsified.
The hackers’ own counts differ. The Cyber Partisans say at least 393,881 Russian citizens had been killed in the war as of 27 August 2026. They counted only deaths where military action or its consequences were given as the cause.
Silent Crow puts the figure at 450,100. Its count also includes non-combat deaths among military personnel, deaths recorded as terrorist acts, and people registered in Russia who died in occupied territory or in Ukraine without a clear cause.
All the totals are broadly in line with earlier estimates. A database compiled by Mediazona and the BBC’s Russian service has identified around 286,000 dead servicemen by name, a list it acknowledges is incomplete. A study by Meduza and Mediazona based on inheritance records estimated about 350,000 deaths by the end of 2025.
British defence intelligence estimated in September that about 500,000 Russian soldiers had been killed.
Janis Kluge, head of the Russia and Eurasia division at the German Institute for International and Security Affairs, told the Guardian the data “looks authentic” and called it the biggest leak yet on Russian casualties.
The records are likely to understate the toll. Soldiers listed as missing do not appear until they are formally declared dead, which can take a long time, and Kluge said deaths typically take about six months to reach official records.
“We are probably at this time closer to 500,000 killed Russian soldiers than 400,000,” he said.
Causes of death on official documents also do not always reflect what actually happened, which means no single count from the data can be treated as definitive.
The records show the losses falling unevenly across Russia. In Buryatia, Tuva and Zabaykalsky Krai, three poorer regions in eastern Russia, war deaths made up about a third of all deaths among men aged 18 to 49 between the start of the invasion and mid-2024. In Moscow and St Petersburg, the share was about 10%.
Deaths also climbed as the war went on. Kluge said that in several months in late 2024 and 2025 more than 15,000 soldiers were killed, or about 500 a day, higher than most outside estimates had suggested.
The 412,576 figure is greater than the roughly 405,000 American military deaths in the second world war.
The leak comes as Russian and Ukrainian negotiators prepare to meet in Abu Dhabi on Tuesday for their first US-brokered talks in nine months. Neither Vladimir Putin nor Volodymyr Zelensky will attend, while Donald Trump’s envoys Steve Witkoff and Jared Kushner are expected to take part.
Witkoff said the talks would cover a “post-war security arrangement, de-escalation” and humanitarian issues. Moscow has continued to demand that Ukraine withdraw from the parts of the Donbas region it still holds, and earlier rounds of talks made little progress.
European governments fear the discussions could stray into wider questions of European security, including Russia’s long-standing demand that Nato reduce its military presence in countries near its borders. France says it will take part in the negotiations, but the Kremlin has denied this.