When chatbots are deployed to automate customer service, it is nearly inevitable that situations will arise in which they struggle to understand customer requests. Unfortunately, the onus of resolving such conversational breakdowns tends to fall on either the customer or the chatbot alone, turning customer–chatbot interaction into a frustrating and often unsuccessful guessing game. Despite indications that customers would be open to collaboration, we know little about repair strategies that involve the customer and chatbot working together to resolve breakdowns. Our research addresses this gap by investigating the design and impact of collaborative repair strategies in customer–chatbot interaction. Drawing upon an integration of the theory of least collaborative effort with research on human–machine communication and customer service chatbots, we propose a novel repair strategy design, instantiate it in the chatbot of a large insurance company, and conduct a naturalistic summative evaluation through a randomized field experiment. Overall, our results suggest that a collaborative repair strategy can lead to more breakdowns being resolved as well as mitigate the negative impacts of breakdowns on key customer outcomes. Our research offers a new way of thinking about customer–AI service interactions by shifting the narrative from confrontation to collaboration, extends the theory of least collaborative effort by integrating the perspective of customer–chatbot interaction, and provides in-depth insights into breakdown and repair in real-world conversations between customers and chatbots.