When Alexandra Dubois, Senior Tax Manager at Booking.com, describes how the company approached e-invoicing, she's quick to correct the framing most tax teams default to.
"I don't necessarily see billing as a tax thing where tax is the [only] owner," she told Fonoa's Rob van der Woude in a recent conversation. "It has a very strong tie to tax. But it has much wider implications for our company, our customers, and our vendors."
That reframe sits at the center of everything Booking.com got right. Watch the full conversation in the e-invoicing compliance strategy webinar with Booking.com.
Key takeaways from Booking.com's e-invoicing journey
1. The pain had to be shared before the business case landed
Booking.com didn't move to a strategic e-invoicing solution because the tax team identified a gap. They moved because a series of stressful, manual, cross-functional implementations made the problem visible to everyone.
"It wasn't just tax that felt the pain [of manual e-invoicing launches]. A lot of teams were like, this is not really a workable way to do this."
—Alexandra Dubois, Senior Tax Manager at Booking.com
Going country by country with devoted finance FTEs to manage manual processes was never going to scale. But it took the pressure of real implementations, in Hungary, then Portugal, then Malta in quick succession, to build the internal consensus that something had to change.
The business case didn't come from a spreadsheet. It came from evidence.
2. Tax data is a cross-functional problem dressed up as a tax problem
One of the most consistent challenges Alexandra flagged: tax-relevant data at Booking.com was scattered across systems, some focused on transactions, others on financials. Bringing it together required building bridges between teams that hadn't previously needed to collaborate.
"You really have to get all the right perspectives in place to really make [an e-invoicing] solution work. It's not just a tax problem, or an IT problem, or a finance problem."
—Alexandra Dubois
That's true of most large e-invoicing programs. The requirements start in tax, but the execution touches product, engineering, legal, risk, customer service, and finance. Teams that treat it as a tax handoff to IT tend to hit the same wall over and over.
3. Centralized data is the real foundation, not the technology layer
Booking.com chose to work with Fonoa after running an RFP process, but Alexandra is clear that selecting a vendor was only part of the work. Read the full story in the Booking.com Transport e-invoicing case study. Before any integration could happen, the team had to centralize and orchestrate its data into one place.
Interestingly, the e-invoicing program ended up positioning Booking.com as an internal frontrunner on data centralization, ahead of where the broader company strategy had gotten.
That's a pattern worth noting. E-invoicing mandates, because they require clean transactional data at speed, force a level of data maturity that benefits the entire organization, not just the compliance function.
4. "Buy still requires build." And that's fine (if you're honest about it)
The decision to work with an external vendor rather than build in-house didn't remove implementation effort from Booking.com's plate. It shifted it.
"Buy versus build, although buy still requires build," Alexandra said plainly.
What the vendor relationship did do was eliminate the need to rebuild the integration from scratch for each new country. The goal was one integration, then minimal customization per jurisdiction. That architecture is what made the speed improvement possible. Implementations that previously took months now take days or weeks.
The remaining complexity, ambiguous go-live dates, evolving requirements, last-minute data specifications, isn't a technology failure. It's the nature of a regulatory environment that's still maturing.
5. Conversion versus compliance is a real tension, and you have to name it directly
Getting the right data to comply with e-invoicing requirements sometimes means asking customers for more information during their booking flow. That creates friction with commercial teams focused on conversion rates.
Alexandra's approach wasn't to win the argument on technical grounds. It was to tell the story of what was coming.
"[Aligning teams] was a lot about how you tell the story, why we should do this, [and] setting the scene."
—Alexandra Dubois
Framing compliance as a future-looking risk, rather than a current cost, gave the business case traction. Pointing to the pipeline of mandates ahead made the data investment feel like preparation rather than disruption.
6. Implementation speed is the metric that matters most now
Before Fonoa, getting ready for a new mandate could take months. After establishing the integration and standardized approach, the same work can happen in days in the best cases, and a few weeks in others.
That shift in speed changes how the tax team operates. They can respond to mandates with confidence rather than stress, and they can sell that confidence internally to the engineering teams who need to prioritize the work.
"We know it works," Alexandra said. "We have a solid game plan, a standardized way of working, and a strategic solution."’
The key takeaway: The next wave is real-time, transaction-level, and continuous
Looking ahead, Alexandra sees the trajectory clearly. Tax authorities are becoming more data-driven and more technology-focused. Reporting intervals are compressing. Some jurisdictions are already pushing for transaction-level data on a one-day deadline, with continuous access requirements.
"We need to do more, share more, be more prepared, and react much faster, real-time at a transactional level," she said.
The companies positioned to handle that environment are the ones that have already done the foundational work: clean data, solid integrations, cross-functional alignment, and a vendor relationship built for flexibility.
"And as tax authorities become more data-driven and demand real-time reporting, it all comes down to having the right data and the right foundation. We're ready."
—Alexandra Dubois, Senior Tax Manager
For Booking.com, that foundation is in place. The work now is staying ahead of what comes next.
