Historically, the speed, expense, and efficiency of sperm sex-sorting procedures have dictated that a commercial product offering could only be economically viable if provided at relatively low sperm dosage (2 million sperm per straw). A lower conception rate was also accepted as part of this process and previous field trials have indicated only a marginal fertility increase when dosage was increased up to 10 million sperm per dose. However, recent technological improvements in sperm sorting efficiency and proprietary processing procedures that have enhanced sperm survival, collectively marketed as SexedUltra, may result in increased fertility in response to increased sperm dose rate. We hypothesized that increasing sperm dosage from 2 to 4 million sperm per straw with SexedUltra would increase conception rate in heifers. Using a split-ejaculate technique, ejaculates from 6 Holstein bulls were sex-sorted according to SexedUltra procedures and frozen at 2 and 4 million sperm per 0.25-mL straw or processed as unsorted sperm at 15 million sperm per 0.5-mL straw. Treatments were distributed among 16 herds for use at first or second service in Holstein heifers. Within herd, equal dosages of each treatment were allocated for each bull selected for use. Outcomes to artificial insemination (n = 5,476) were analyzed in a mixed model ANOVA with the fixed effect of treatment and random effects of herd, bull, and the 2-way interactions of herd and bull with treatment. Conception rates of 2 million (40.6%, n = 1,831) and 4 million (46.4%, n = 1,852) SexedUltra treatments were less (P < 0.05) than those obtained with unsorted sperm (57.8%, n = 1,793). The 4 million dosage of SexedUltra resulted in a greater (P < 0.05; Student’s t-test) conception rate compared with the 2 million dosage. Conception rates of SexedUltra are improved by a 4 million sperm dosage but remain significantly less than those obtained with unsorted semen.