Holstein bull calves (n = 48, 2–3 d of age) were fed milk replacer powder (MR) at 0.66 kg DM/d for 46 d and 0.33 kg/d for 3 d (MRM) or 0.85 kg/d for 5 d, 1.07 kg/d for 37 d, and 0.53 kg/d for 7 d (MRH), reconstituted to 14% DM. Calf starters (CS), offered from d 1, were a pellet containing 10% starch or a textured feed with whole corn and oats containing 40% starch (HS). Water was available at all times. From 0 to 8 wk, calves were housed in individual pens. From 9 to 16 wk, calves were grouped (4 calves/pen) within treatment and fed 95% of the same CS plus 5% chopped grass hay. During the last 5 d of wk 5, chromic oxide was added to MR at each feeding of 5 calves per treatment to estimate digestibility. During wk 8, fecal grab samples were taken from the same calves once daily for 5 d. During wk 11, 13, and 16, fecal samples were carefully collected from the floor of all group pens once daily for 5 d. All post-weaned fecal samples were analyzed for acid-insoluble ash to estimate digestion. Data were analyzed as a 2 × 2 factorial arrangement of MR and CS in a repeated measures mixed model ANOVA. Digestion of most nutrients increased with age and CS intake. Feeding MRH during wk 0–8 reduced (P < 0.01) digestion of NDF (33.0 vs. 50.4%), ADF (22.7 vs. 41.5%) and starch (75.0 vs. 84.4%). Feeding HS during wk 0–8 increased (P < 0.05) digestion of DM (80.8 vs. 72.6%), OM (81.5 vs. 73.3%), starch (84.8 vs. 74.6%), and CP (76.6 vs. 71.6%), and reduced (P < 0.05) digestion of NDF (36.4 vs. 47.0%) and ADF (26.5 vs. 37.7%). From wk 11–16, feeding MRH reduced (P < 0.01) digestion of DM (77.9 vs. 79.9%), OM (78.8 vs. 80.7%), CP (80.4 vs. 83.2%), fat (85.8 vs. 87.4%), NDF (36.6 vs. 60.0%) and ADF (25.2 v. 57.9%). From wk 11–16, feeding HS increased (P < 0.01) digestion of DM (82.1 vs. 75.7%), OM (83.0 vs. 76.4%), CP (84.0 vs. 79.6%), and reduced (P < 0.05) digestion of starch (96.2 vs. 97.5%), NDF (48.3 vs. 66.6%), and ADF (47.6 vs. 62.4%). Feeding large amounts of MR inhibited OM and fiber digestion to 4 mo of age whereas high CS increased nutrient digestion. Changes to MR feeding programs should consider post-weaning digestion.