Ibaraki Prefecture was the first prefecture of Japan and in the Kantō region to introduce a partnership registry for same-sex couples, as well as the second in the country to pass LGBT-inclusive nondiscrimination protections.

In January 2019, the Government of Ibaraki Prefecture announced it was considering introducing a partnership system for same-sex couples in April 2019.^[1][2][3] In March 2019, Governor Kazuhiko Ōigawa expressed his personal support for the introduction of such a scheme.^[4] The Ibaraki Prefectural Assembly began examining legislation to this effect in June 2019.^[5] The prefecture has offered partnership certificates since July 1, 2019, which made it the first prefecture to do so.^[6][7] As of June 2022, at least 71 partnerships were registered in Ibaraki Prefecture.^{[citation needed]}

On 18 August 2022, the Ibaraki prefectural government announced they would recognize Saga Prefecture's partnership certificates, becoming the first prefectures to do so.^[8] Similar agreements were signed by Ibaraki with Tochigi and Gunma on 20 December,^[9] Mie on 31 January 2023,^[10] and Toyama.on September 4, 2023.^[11] An agreement was signed by the prefecture with the city of Saitama in Saitama Prefecture on October 30, 2023.^[12] On October 23, 2024, the prefectural government announced its accession to the Partnership System Inter-Municipality Collaboration Network to mutually recognize the registries of 18 other prefectures and 150 municipalities.^[13]

In March 2019, legislation banning discrimination against "sexual minorities" was passed in Ibaraki Prefecture.^[14][15]

• "Implementing the Ibaraki Partnership Oath System" (in Japanese)