In November 2025, New Mexico became the first U.S. state to implement a universal, no-cost child care subsidy program. This paper estimates difference-in-differences and event-study models to evaluate the impact of universal child care on mothers' short-run labor supply adjustments. Using monthly Current Population Survey data, I find that the reform produced different responses across lower- and higher-skilled mothers. For lower-skilled mothers, the policy increased employment along both the extensive and intensive margins. Conversely, higher-skilled mothers, particularly those who are married, experienced reductions in paid work, with partially offsetting increases in school enrollment. Thus, while universal child care relaxes a binding constraint among disadvantaged families, it acts as an in-kind transfer for their advantaged counterparts.