The population of the province reaches 1,260,204 inhabitants (data from the National Statistics Institute INE 2022), of which 638,807 live in the metropolitan area of the Bay of Cadiz-Jerez and 273,811 in the metropolitan area of the Bay of Algeciras.

Eight of its towns have more than 60,000 inhabitants (Cádiz, San Fernando, El Puerto, Chiclana, Sanlúcar, Jerez, Algeciras and La Línea de la Concepción).

At the Andalusian level, the province has the highest percentage of population in urban centres, 59.4%.

Its population density is 169.38 inhabitants/km².

The province also attracts a large floating population during the summer season.