A cotton cultivar, designated DPX 08Q818F, is disclosed. The invention relates to the seeds of cotton cultivar DPX 08Q818F, to the plants of cotton DPX 08Q818F and to methods for producing a cotton plant produced by crossing the cultivar DPX 08Q818F with itself or another cotton variety. The invention further relates to hybrid cotton seeds and plants produced by crossing the cultivar DPX 08Q818F with another cotton cultivar.