Heathrow's AI WhatsApp Assistant Hallie Now Handles Most Traveler Inquiries

Heathrow Airport's AI assistant Hallie now handles the vast majority of traveler inquiries via WhatsApp, driving phone calls down to 10 percent of total inquiries by March 2026. Prior to Hallie's launch, 70 percent of customer inquiries at the UK's busiest airport were handled by phone.

The shift reflects three years of deepening Heathrow's partnership with Salesforce to deploy generative and agentic AI for customer service.

Peter Burns, Heathrow's director of digital, e-commerce, and marketing, said he wanted to improve customer service at Europe's busiest airport where demand keeps increasing. "As we grow capacity, we have to find a technology solution," Burns said. Nearly 85 million travelers passed through Heathrow Airport in 2025, many with questions about security wait times, nearby amenities such as Starbucks locations, and retrieving bags left at security.

The airport deployed Salesforce Service Cloud in July 2009. By July 2021, Heathrow's customer and marketing data had been uploaded to Salesforce's real-time data platform, giving employees live views of passenger data.

AI deployment began in January 2023 with two internal use cases: autonomously drafting replies to customer inquiries and creating case wrapups. Heathrow first implemented Salesforce's generative and agentic AI products in 2023. By late 2023, Salesforce's Agentforce was deployed in Heathrow's contact center to assist human agents with writing responses and generating summaries after cases were resolved.

Hallie launched in March 2025. The assistant handles traveler inquiries via WhatsApp, answering questions about upcoming flights, airport amenities, terminals, and security line lengths. Hallie is set to expand to Heathrow's website and app later in 2026.

Heathrow added more internal data to Salesforce's data platform in July 2024, enabling real-time flight-tracking data for customers. The airport's database contains 500 articles outlining processes that Agentforce pulls from. Some policies took several months to gather, update, and implement, Burns said.

Salesforce has met with Heathrow's team in-person about once per quarter since 2009, Paul O'Sullivan said. Salesforce and Heathrow have regular virtual catch-ups every other week. Their meetings in recent years have focused on observing contact agents' workflows and identifying pain points where AI could be applied.

Paul O'Sullivan said it is critical for executive leadership, product managers, engineers, and representatives from security, data, and cloud teams to be on the same page before deploying tools like Agentforce. "The reality is these agents need to be exactly like you and I, and how we work, because we're constantly learning," O'Sullivan said.

Customer service has been a popular use case for generative AI across industries since the debut of ChatGPT in 2022, Bern Elliot said.

"You don't have to connect very many dots to get from what you deployed to what is the measurable improvement," Elliot said. "Having AI-ready data is a huge issue," he added. Burns said Heathrow worked closely with O'Sullivan and his team of UK-based engineers to test and improve the airport's AI capabilities before Hallie's launch.

"We aren't letting the agent go out into the open web and pull out other information," Burns said. Hallie's guardrails limit it to scraping data from Heathrow's website and internal database to ensure accuracy, as external sources could contain inaccurate or out-of-date information.