Pink bollworm (PBW) diapause patterns were studied from 1996-1998 in three West Texas cotton production areas. At Pecos, 12.3 and 57.1 percent of larvae collected from bolls tagged as blooms on August 15 were in diapause in 1996 and 1997, respectively. At St. Lawrence, 57.1% were in diapause for the same date in 1996. Very light infestations prevented diapause estimates for El Paso in 1996 and 1998 (in part), St. Lawrence (1997, in part, and 1998) and Pecos in 1998. Estimates of diapausing larvae per acre generated on sample dates were calculated by multiplying (# larvae per boll) x (# susceptible bolls per acre) x (% of the larval population in diapause). Estimates of total diapausing larvae per acre generated through the sample period were made by interpolating values for non-sample dates and summing them. Values ranged from 834 to 215,932 diapausing larvae per acre under different crop and pest conditions.