[4] Culcita macrocarpa is endemic to Portugal and Spain, both on the Iberian Peninsula and Macaronesia.

In the Iberian Peninsula it is found in the north Cantabrian and Asturian coasts, northern Galicia and in mountainous areas around Porto and the Province of Cádiz.

[5] It grows on siliceous rocky slopes, especially in deep valleys under evergreen forest and near coastal areas, sometimes in scrubland up to 1,100 metres (3,600 ft) elevation.

This species requires shade and warm temperatures all year round, with high atmospheric humidity to flourish.

[1] It grows in all types of soils but avoids limestone substrates and is especially common on the herbaceous layer of high elevation montane forests of the Azores.