A cotton cultivar designated Acala ULTIMA EF is disclosed. The invention relates to the seeds of cotton cultivar Acala ULTIMA EF, to the plants and plant parts of cotton Acala ULTIMA EF and to methods for producing a cotton plant produced by crossing the cultivar Acala ULTIMA EF with itself or another cotton variety. The invention further relates to hybrid cotton seeds and plants produced by crossing the cultivar Acala ULTIMA EF with itself or with another cotton cultivar.