Objectives This mixed-method study aimed to understand the effectiveness of linkage to biopsy and treatment in women with a high-risk mammography result (Breast Imaging Reporting and Data System, BI-RADS 4 and 5) in the national telemammography programme and to explore women's experiences during this process. Setting Quantitative component: we collected and linked health data from the telemammography reading centre, the national public health insurance, the national centre for disease control and the national referral cancer centre. Qualitative component: we interviewed participants from different regions of the country representing diverse social and geographical backgrounds. Participants Quantitative: women who underwent telemammography between July 2017 and September 2018 and had high-risk results (BI-RADS 4-5) were collected. Qualitative: women with a high-risk telemammography result, healthcare providers and administrators. Outcomes measures Quantitative: we determined biopsy and treatment linkage rates and delays. Qualitative: we explored barriers and facilitators for obtaining a biopsy and initiating treatment. Results Of 126 women with high-risk results, 48.4% had documentation of biopsy and 37.5% experienced a delay of >45 days to biopsy. Of 51 women diagnosed with breast cancer, 86.4% had evidence of treatment initiation, but 69.2% initiated treatment >45 days after biopsy. Travelling to major cities for care, administrative factors and breast cancer misconceptions, among other factors, impeded timely, continuous care for breast cancer. A multidisciplinary and culturally tailored patient education facilitated understanding of the disease and prompt decision making about subsequent medical care. Conclusions Strengthened breast cancer care capacity outside the capital city, standardised referral pathways, ensured financial support for travel expenses, and enhanced patient education are required to secure linkage to the breast cancer care continuum. Robust information systems are needed to track patients and to evaluate the programme's performance.