SETTING: DOTS-reporting tuberculosis (TB) diagnostic centres across Pakistan. OBJECTIVES: To quantitatively investigate the influence of diagnostic centre characteristics on the number of female and male TB suspects registered at diagnostic centres. DESIGN: Ten districts were selected across the four provinces of Pakistan. Data were collected on male and female TB suspects in all diagnostic centres within each district. A structured questionnaire was used to collect data on characteristics of the diagnostic centres. Multiple linear regression analysis was conducted to evaluate the influence of each characteristic on sex differences in the numbers of suspects. RESULTS: Two diagnostic centre characteristics were associated with higher numbers of female than male TB suspects: catering to the local catchment area (P = 0.001) and being accessible on foot (P = 0.002). The following characteristics were associated with higher numbers of male than female TB suspects: being open after 2 pm (P = 0.041), having more than five doctors working at the centre (P = 0.019), and having more than 100 suspects registered per quarter (P = 0.008). CONCLUSIONS: Smaller, local diagnostic centres that are accessible on foot registered more female than male TB suspects. More centralised facilities located further from homes, larger facilities and those with evening opening hours registered more male than female suspects.