We undertake a field experiment that delivers information on electricity pricing to randomly-selected households in Puebla, Mexico. The 20-minute, in-person intervention educated households on how their electricity use translates into pesos on their electricity bill. Households receiving the treatment reduced electricity use, especially those that paid the highest marginal prices. The estimated impacts were durable, with no observed rebound for at least a year. In addition, those with less educational attainment reduced electricity use the most, suggesting that it was newly-acquired knowledge that led to this behavior. Our intervention was tailored for an emerging economy setting and had high acceptance rates. We also find that it is a cost-effective approach to overcoming information barriers that are likely to exist in developing countries that are restructuring their energy sectors.