Secondhand smoke (SHS) exposure causes chronic illness and occurs at a higher prevalence in low-income communities than the general public. In 2018, the U.S. Department of Housing and Urban Development (HUD) instituted a smoke-free housing rule for Public Housing Authorities (PHAs) to address persistent health inequities. However, the success of smoke-free housing requires evidence to inform effective implementation approaches. A mixed-methods, cross-sectional survey was conducted in a national sample of PHAs. Questions focused on housing officials’ use of specific implementation strategies. Adjusted odds ratios were used to assess associations between implementation approaches and variations among PHAs (i.e., region, size, or recency of policy adoption). Qualitative analyses were conducted to assess the perceived effectiveness of implementation strategies. Resident engagement, staff training, and smoking cessation support were the most frequently used implementation strategies. Engagement with local stakeholders was cited less frequently. Enforcement actions were limited with no violations referred to housing court. Support for policy adherence was identified as a sixth implementation strategy. While most PHAs used at least some evidence-informed implementation strategies, a lack of a systematic approach may limit overall effectiveness. Further research is required to resolve implementation barriers experienced disproportionately by a subset of PHAs, and to inform a best practice implementation framework that meets the needs of a heterogeneous population.