As one of the seven suffragans in the ecclesiastical province of the Metropolitan Archbishop of Utrecht, the diocesan territory comprises the north west of the Netherlands, including the cities of Haarlem (capital of North Holland) and Amsterdam (in the same province and Dutch nominal national capital).

[2] The diocese was founded on 12 May 1559, on territory (central and North Holland) canonically split off from the Diocese of Utrecht, which was simultaneously promoted to archbishopric and became its Metropolitan.

In 1592 (during the Eighty Years War, during which the Spanish crown lost Holland) it was suppressed, and its territory was immediately included in the new Dutch Mission sui iuris 'Batavia', soon promoted an Apostolic vicariate.

The cathedral episcopal see of the Diocese of Haarlem–Amsterdam is the Cathedral of Saint Bavo, a minor basilica in Haarlem, which city also has two former cathedrals: Saint Joseph Church and Saint Bavo Church (now a Protestant church).

[3] In 2013, the diocese pastorally served 462,000 Catholics (15.8% of 2,915,000 total) on 2,912 km² in 145 parishes, with 194 priests (161 diocesan, 33 religious), 54 deacons, 557 lay religious (81 brothers, 476 sisters).