Improving access to family planning services is key to achieving many of the United
Nations sustainable development goals. To scale up access in remote areas and urban slums,
many developing countries deploy mobile family planning teams that visit “outreach sites”
several times per year. Visit frequencies have a significant effect on the total number of clients
served and hence the impact of the outreach program. Using a large dataset of visits in
Madagascar, Uganda and Zimbabwe, our study models the relationship between the number
of clients seen during a visit and the time since the last visit and uses this model to analyse
the characteristics of optimal frequencies. We use the latter to develop simple frequency
policies for practical use, prove bounds on the worst-case optimality gap, and test the impact
of the policies with a simulation model. Our main finding is that despite the complexity of the
frequency optimisation problem, simple policies yield near-optimal results. This holds even
when few data are available and when the relationship between client volume and the time
since the last visit is misspecified or substantially biased. The simulation for Uganda shows a
potential increase in client numbers of between 7% and 10%, which corresponds to more than
12,000 additional families to whom family planning services could be provided.