Classified data leaked: over 400,000 Russians killed in the war

The data was shared with, among others, the British newspaperThe Guardian. According to the analysis, 412,576 death certificates contained direct references to the war – through cause-of-death codes or mentions of combat actions and military operations.

Rosstat itself confirmed the leak (admitting that a hacking attack occurred in late October and early November 2026), although it denied that any sensitive data had been compromised. Janis Kluge, an expert from the German Institute for International and Security Affairs (SWP), deemed the data authentic and described it as the largest leak regarding Russian losses to date. He emphasised that in the second half of 2024 and in 2025, there were months with over 15,000 killed, and the actual figure may be closer to 500,000 due to registration delays (approx. six months), as well as unidentified and missing individuals.

The two hacking groups provided slightly different figures: Cyber Partisans – approx. 394,000; Silent Crow – approx. 450,000. The data also shows an uneven distribution of losses: in republics such as Buryatia, Tuva, or Zabaykalsky Krai, the war accounted for approximately one-third of deaths among men aged 18–49, while in Moscow and St Petersburg, the figure was around 10%.

Comparison with Other Sources

Casualty figures in war always vary, as they depend on definitions, methodology, and delays. The Ukrainian side frequently inflates Russian losses by including the wounded in the total tally. At the same time, reliable information from the Russian side cannot be expected, so all data are primarily estimates with a certain margin of error.

Mediazona and BBC Russian recently reported on losses estimated at approx. 286,000 confirmed by name. This is a minimum verified number based on obituaries, family posts, local media, and photographs of graves. Estimates based on probate records indicate higher values – in the region of 335,000–350,000 by the end of 2025, with a trend towards approximately half a million in total.

In turn, British Intelligence speaks of approx. 500,000 killed Russian soldiers, estimating total casualties at around 1.5 million. These figures are very close to those provided by the General Staff of Ukraine: approx. 1.61 million Russian personnel losses (killed + wounded) as of 10 November 2026.

The Rosstat data leak is consistent with independent sources estimating Russian losses, although it must still be considered that the actual number remains unknown. Russia has not published its own casualty data since September 2022, treating it as a state secret. Invariably, however, the losses in the current war are unprecedented in modern Russian history – many times higher than the combined losses of the USSR and Russia in post-WWII conflicts.