Our objectives were to evaluate time to pregnancy for dairy cows managed with the Short-Resynch (SR) or Day25-Resynch (D25R) protocol. Lactating Holstein cows not pregnant after first service from 2 farms were stratified by parity (1 vs. >1) and assigned to the SR (n = 1,533) or the D25R (n = 1,555) treatment. Cows in D25R received GnRH 25 ± 3 d after AI. At 32 ± 3 d after AI, nonpregnant cows from SR and D25R with a corpus luteum (CL) ≥ 15 mm and a follicle ≥10 mm received PGF_2α (PGF), 24 h later PGF, 32 h later GnRH, and 16 h later TAI. Cows without a CL ≥15 mm and/or a follicle ≥10 mm (NoCL cows) received an Ovsynch protocol with 2 PGF treatments and progesterone (P4) supplementation (GnRH⁺CIDR-7 d-CIDR-out+PGF-1 d-PGF-32 h-GnRH-16 h-TAI). Circulating P4 concentration was determined (n = 659 cows) at the GnRH treatment before TAI. Binomial data were analyzed using logistic regression and time to pregnancy [only cows with 210 d at risk after first AI (D25R = 543; SR = 512)] using Cox’s proportional hazards regression. A greater (P < 0.01) proportion of inseminations were conducted at detected estrus in SR (60.4%) than in D25R (49.8%) but, P/AI did not differ (P = 0.14; D25R = 40.4%; n = 1,191 vs. SR = 37.8%; n = 1,489). More cows had a CL at NPD (P < 0.01) in D25R (84.3%; n = 1,139) than SR (78.5%; n = 939). Pregnancies per AI differed for all TAI combined (P = 0.01; D25R = 40.7% vs. SR = 35.4%), for CL cows (P < 0.01; D25R = 40.9%vs. SR = 32.8%), and tended to differ for NoCL cows (P = 0.06; D25R = 39.1% vs. SR = 44.6%). Treatment did not affect pregnancy loss (P > 0.10). The proportion of cows with P4 < 0.5 ng/mL at the GnRH before TAI did not differ (P > 0.10). The hazard of pregnancy was not affected by treatment (P = 0.77; HR = 0.98, 95% CI: 0.85–1.13) or parity (P = 0.71; HR = 1.01, 95% CI: 0.87–1.16). Median days to pregnancy were 75 and 74 for SR and D25R, respectively. The proportion of nonpregnant cows 210 d after first service was similar (P = 0.20) for SR (23.6%) and D25R (20.3%). In conclusion, the Short-Resynch protocol resulted in more inseminations at detected estrus and similar time to pregnancy than the D25-Resynch protocol in spite of a reduction in P/AI for TAI services for CL cows. Supported by NYFVI Project FVI17–013 and USDA Hatch NYC127434.