Many women in low‐income countries cannot afford maternal healthcare services. Changamka, a Kenyan company, developed an electronic, stored‐value card to help pregnant women save for maternal healthcare at a Nairobi hospital. This paper reports results from a mixed‐methods process evaluation of the card's implementation. The study found high levels of uptake and identified several benefits of the program, such as facilitating payment for services. The evaluation also identified several challenges. Most users completed only one transaction before discontinuing card use; only 6% of women who acquired the card used it to pay for delivery, and slightly less than 1% used it as it was originally intended—to pay for several antenatal care visits and for delivery. According to respondents, the main reason for this discontinuation was a lack of understanding about how to use the card. Users were, on average, of a higher socioeconomic and educational status than non‐card users. Most users obtained the card in their third trimester, and among those who used the card to save for delivery, most started to do so too late in pregnancy to accumulate sufficient savings to pay for that service. Copyright © 2015 John Wiley & Sons, Ltd.