The objective of this study was to determine the effect of limiting hay on the development of the rumen in pre-weaned Jersey calves. Jersey bull calves (n = 13) at 4 weeks of age were individually housed and randomly assigned to one of 2 treatments in a randomized complete block design. One group was limit-fed (LF) alfalfa hay at 90g/d while the second group was fed alfalfa hay ad libitum (AL). All calves were fed 1300 g/d of milk replacer (26% CP/18% Fat) and were fed a texturized calf-starter ad libitum. Weekly, calves were weighed and a blood plasma sample was taken for metabolite analysis. After a calf consumed 680g/d of starter for 3 consecutive days, calves were ruminally dosed with a rumen pH logger and ruminal pH was recorded every 2 min for 7 d. Data were analyzed using the Mixed procedure of SAS 9.4. Average daily gain was not significantly different between AL and LF (0.87 ± 0.03 vs. 0.85 ± 0.04 kg/d, respectively; P = 0.55). Mean rumen pH did not differ between AL and LF treatments (6.23 ± 0.17 vs. 6.13 ± 0.22, respectively; P = 0.68) and there was no difference between duration of time rumen pH <5.8 between AL and LF (259 ± 178 vs. 318 ± 228 min/d, respectively; P = 0.83). Standard deviation of rumen pH was greater in LF than AL (0.33 ± 0.02 vs. 0.25 ± 0.02, respectively; P = 0.05). Additionally, hay intake was negatively correlated to standard deviation of rumen pH (r = −0.93; P = 0.02). This study demonstrates that limit-feeding hay can help maintain mean rumen pH in pre-weaned dairy calves. Although mean rumen pH is similar between AL and LF treatments, the higher standard deviation indicates rumen pH is more variable when hay is limit-fed.