Objectives. To estimate changes in national breastfeeding trends immediately before and after COVID-19‒related workplace closures in early 2020. Methods. The implementation of shelter-in-place policies in early 2020, when 90% of people in the United States were urged to remain at home, represents a unique natural experiment to assess the pent-up demand for breastfeeding among US women that may be stymied by the lack of a national paid leave policy. We used the 2017-2020 Pregnancy Risk Assessment Monitoring System (n = 118 139) to estimate changes in breastfeeding practices for births occurring before and after shelter-in-place policies were implemented in the United States. We did this in the overall sample and by racial/ethnic and income subgroups. Results. There was no change in breastfeeding initiation and a 17.5% increase in breastfeeding duration after shelter-in-place, with lingering effects through late 2020. High-income and White women demonstrated the largest gains. Conclusions. The United States ranks worse than similar countries when it comes to breastfeeding initiation and duration. This study suggests that this is partly attributable to inadequate access to postpartum paid leave. This study also demonstrates inequities introduced by patterns of remote work during the pandemic. (Am J Public Health. 2023;113(8):870-873. https://doi.org/10.2105/AJPH.2023.307313).