BACKGROUND: Patient follow-up is a routine component of clinical practice and valuable for evaluating the effectiveness of interventions, but because of the broad dispersion of health facilities and lack of standardised medical reporting in Malawi, collecting patient outcome data can be challenging. Increasing accessibility and affordability of mobile technology in resource-poor settings may facilitate patient follow-up in the community. The objective of this study was to evaluate the potential utility of mobile phones for collecting follow-up clinical data from parents or caregivers of acutely unwell under-5 children, for intervention evaluation purposes. METHODS: Parents' or caregivers' mobile phone numbers were obtained by health surveillance assistants (HSAs) during study enrollment. Guardians who provided a telephone number were contacted by the study team to establish re-consultations or hospitalisations of their child(ren) within 14 days of recruitment. Health records at village clinics and higher-level health facilities were hand-searched to identify or confirm presentations and abstract clinical data. RESULTS: 87 out of 149 (58.4%) guardians provided a mobile telephone number, of whom the study team could contact 44 (29.5%). Seven guardians stated they took their child for further treatment: three of these returned to village clinics and four presented to secondary care facilities; attendance could only be confirmed from health records for one child. CONCLUSIONS: With continued expansion of cellular network coverage and mobile ownership in Malawi, mobile phones may facilitate collection of patient outcomes for intervention evaluation purposes. Future consideration should also be given to integrating mobile technologies into HSA clinical practice.