Anaerobic digesters can provide renewable energy and reduce greenhouse gas emissions from manure management. Government policies that encourage digester adoption by livestock operations include construction cost-share grants, renewable electricity subsidies, and carbon pricing (offset) programs. However, the effectiveness and efficiency of these policies is not well understood. For the U.S. dairy sector, we compare predicted digester adoption rates, carbon emission reductions, renewable electricity generation and sales, and net returns and social benefits of several policies. We find that a carbon pricing policy provides the greatest net social benefit for a range of assumptions about the benefits of carbon reductions and renewable energy.