September 9, 2025

Information Cutoff: 7:00 pm ET

Jennie Olmsted, Christina Harward, Angelica Evans, Olivia Gibson, Daria Novikov, and Karolina Hird

Russian territorial gains have become less costly over the last four months compared to Spring 2025 as Russian forces are sustaining a lower casualty rate per square kilometer seized. Ukrainian Commander-in-Chief General Oleksandr Syrskyi reported on September 9 that Russian forces have suffered 299,210 casualties since January 2025. ISW assesses that Russian forces gained a total of 1,910.39 square kilometers of territory in Ukraine in May, June, July, and August 2025, and the Ukrainian General Staff’s daily Russian casualty reports indicate that Russian forces suffered 130,160 casualties in that same time frame, averaging to 68 casualties per square kilometer seized between May and August 2025. ISW assesses that Russian forces seized 499.28 square kilometers in May 2025; 465.8 square kilometers in June 2025; 445.88 square kilometers in July 2025; and 499.43 in August 2025. Ukrainian General Staff data indicates that Russian forces suffered 35,370 casualties in May 2025; 32,680 in June 2025; 33,230 in July 2025; and 28,880 in August 2025. This means that Russian forces averaged roughly 71 casualties per square kilometer in May 2025; 70 casualties per square kilometer in June 2025; 75 casualties per square kilometer in July 2025; and 68 casualties per square kilometer in August 2025. Russian casualty rates per square kilometer gained have substantially decreased over the last four months compared to January through April 2025, when Russian forces were losing 99 casualties per square kilometer.

Russian casualty rates per square kilometer peaked in the first four months of 2025 as Russian forces fought to maintain the intensified pace of offensive operations they began in the Fall of 2024. Russian forces lost an estimated average of 59 casualties per square kilometer gained during the first four months of their intensified 2024 offensive campaign (between September and December 2024). Russian forces concentrated their offensive operations in western Donetsk Oblast and counteroffensive operations in Kursk Oblast in Fall 2024 and made tactically significant advances in the Kursk, Pokrovsk, Kurakhove (now Novopavlivka), and Velyka Novosilka (now Velykomykhailivka) areas. Russian forces were still frequently using armored vehicles to advance during Fall 2024, which likely helped preserve some Russian lives. Russian forces were mainly advancing in small infantry assaults during Fall 2024, as they were as of August 2025, but Russian forces largely abandoned use of armored vehicles in late 2024 and early Spring 2025, and this change in tactics likely contributed to increased Russian casualty rates in the first few months of 2025.

Russian advances began to slow during the first four months of 2025 as Russian casualties remained consistent, resulting in a higher Russian casualty rate between January and April 2025. Russian forces suffered an average of 99 casualties per square kilometer gained in January, February, March, and April 2025. Russian advances significantly increased in March 2025 with the elimination of the Ukrainian salient in Kursk Oblast, which coincided with the temporary cessation of US intelligence sharing with Ukraine, although Russian advances on average decreased between January, February, and April 2025. Russian gains also slowed as Russian forces came up against better-defended Ukrainian positions in and around larger towns such as Kupyansk, Chasiv Yar, Toretsk, and Pokrovsk during Spring 2025. Russian gains slowed by 45 percent between January and April 2025 compared to gains between September and December 2024, although Russian casualty rates only decreased by 10 percent during those four months. Russian forces also began to more frequently use unarmored vehicles such as motorcycles and open-air buggies during this time, and therefore began to suffer a higher killed-in-action (KIA) to wounded-in-action (WIA) ratio.

• Russian territorial gains have become less costly over the last four months compared to Spring 2025 as Russian forces are sustaining a lower casualty rate per square kilometer seized.
• Russian casualty rates per square kilometer peaked in the first four months of 2025 as Russian forces fought to maintain the intensified pace of offensive operations they began in Fall 2024.
• Russian advances began to slow during the first four months of 2025 as Russian casualties remained consistent, resulting in a higher Russian casualty rate between January and April 2025.
• Russian forces began to make quicker gains in May 2025 and have sustained a faster rate of advance over the last four months as Russian casualties marginally decreased, although Russian forces continue to advance at footpace.
• Russian casualty rates have likely decreased in Ukraine due to Russia’s renewed emphasis on using UAVs to generate some effects of battlefield air interdiction (BAI), largely led by UAV operators of Russia’s Rubikon Center for Advanced Unmanned Technologies.
• Recent Russian polling suggests that support among the Russian population for the war remains high despite growing casualties and relatively slow advances on the battlefield.
• Ukraine continues to strike Russian energy infrastructure.
• Ukrainian forces reportedly conducted a combined strike against three Russian command posts in and near occupied Donetsk City on September 8.
• Russian State Duma officials are engaging in a top-down Kremlin-organized effort to threaten Finland.
• Russian forces conducted a strike against a mobile pension dispersal point in Donetsk Oblast that killed and wounded dozens of mostly elderly civilians.
• Ukrainian forces recently advanced in the Kostyantynivka-Druzhkivka tactical area. Russian forces recently advanced near Novopavlivka.

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