Abstract Efforts to enhance carbon sequestration, including afforestation and reforestation, are critical strategies to meet the New York State (NYS) climate goals. In NYS, converting underutilized lands to mature forests can mitigate 4.9 million metric tons of CO2 annually, but 97% of suitable lands are privately owned. These mitigation figures do not consider landowner willingness to grow mature forest. Drawing on a survey of 979 NYS landowners, we explored interest in growing mature forest, potential barriers, and how they can be mitigated. Survey results indicate landowners seem reasonably interested (about one-third were “very interested”) in converting at least some of their land to mature forest for carbon sequestration. Respondents were most willing to convert land in young forest and shrubland and least willing to convert fallow fields, grassland, and agricultural land. Key barriers are related to inadequate labor and financial resources. Incentives focused on finances most increase willingness but only modestly so. Study Implications: Land availability for carbon sequestration can only be realistically understood if we consider private landowner willingness to grow forests. We observed relatively strong enthusiasm for converting young forest and shrubland. Land conversion proponents could tailor management and communication strategies to owners of these land types. Conversion is tied to overcoming negative attitudes about the potential conflict between current management and managing for carbon sequestration and providing resources for conversion. Landowner willingness was less when the agricultural footprint was greater. With much farmland in NYS, the amount of land available for reforestation may be lower than what landcover-based estimates suggest.