• September 12, 1895 — The village of Yuge broke off the village of Uoshima.
• April 1, 1897 — The Noma District was absorbed into the Ochi District. (1 town, 38 villages)
• July 1, 1899 — The village of Kameyama broke off from the village of Uzuura. (1 town, 39 villages)
• January 1, 1908 — The village of Hashihama gained town status. (2 towns, 38 villages)
• January 1, 1908 — The village of Kikuma gained town status. (3 towns, 37 villages)
• October 1, 1917 — The village of Sakurai gained town status. (4 towns, 36 villages)
• February 11, 1920 — The town of Imabari and the village of Hiyoshi merged to form the city of Imabari. (3 towns, 35 villages)
• April 1, 1925 — The village of Kasen merged into the town of Kikuma. (3 towns, 34 villages)
• February 11, 1933 — The village of Chikami merged into the city of Imabari. (3 towns, 33 villages)
• January 1, 1940 — The village of Tachibana merged into the city of Imabari. (3 towns, 31 villages)
• November 1, 1940 — The village of Higashihakata gained town status to become the town of Hakata. (4 towns, 31 villages)
• August 1, 1952 — The village of Miyakubo gained town status. (5 towns, 30 villages)
• January 1, 1953 — The village of Yuge gained town status. (6 towns, 29 villages)
• March 31, 1954 — The villages of Nibukawa, Kuwa, Kanbe, and Ryūoka merged to form the village of Tamagawa. (6 towns, 26 villages)
• March 31, 1954 The villages of Tsukura, Kameyama, Uzuura, and Ōyama merged to form the town of Yoshiumi. (7 towns, 23 villages)
• March 31, 1954 — Parts of the village of Ōyama merged into the town of Miyakubo. (7 towns, 22 villages)
• January 1, 1955 — The village of Nishihakata merged into the town of Hakata. (8 towns, 20 villages)
• February 1, 1955 — The towns of Sakurai, Tomita, the villages of Shimizu, Hitaka, Noma, and the town of Hashihama merged into the city of Imabari. (6 towns, 16 villages)
• March 31, 1955 — The villages of Ōi and Konishi merged to form the town of Ōnishi. (7 towns, 14 villages)
• March 31, 1955 — The villages of Setozaki and Moriguchi merged to form the village of Kamiura. (7 towns, 13 villages)
• March 31, 1955 — The villages of Kagami and Miyaura merged to form the town of Ōmishima. (8 towns, 11 villages)
• March 31, 1955 — The village of Kameoka merged into the town of Kikuma. (8 towns, 10 villages)
• August 1, 1955 — parts of the town of Yoshiumi (Umashima Island) merged into the city of Imabari.
• March 31, 1956 — The villages of Kamiasakura and Shimoasakura merged to form the village of Asakura. (8 towns, 9 villages)
• September 23, 1956 — The village of Okayama merged into the town of Ōmishima. (8 towns, 8 villages)
• March 1, 1960 — The village of Namikata gained town status. (9 towns, 7 villages)
• May 1, 1960 — Parts of Oura in the town of Namikata merged into the city of Imabari.
• April 1, 1962 — The village of Tamagawa gained town status. (10 towns, 6 villages)
• April 1, 1964 — The village of Kamiura gained town status. (10 towns, 5 villages)
• October 1, 2004 — The towns of Yuge, and the villages of Ikina, Iwagi, and Uoshima merged to form the town of Kamijima. (10 towns, 2 villages)
• January 16, 2005 — The towns of Hakata, Kamiura, Kikuma, Miyakubo, Namikata, Ōmishima, Ōnishi, Tamagawa and Yoshiumi, and the villages of Asakura and Sekizen merged into the expanded city of Imabari. (1 town)

34°15′47″N 133°10′41″E / 34.26306°N 133.17806°E / 34.26306; 133.17806