International eBilling Compliance: Why the Rules Look Different in Every Country

Puntos clave

• “International eBilling compliance” isn’t one process. At its simplest, it means understanding the region- and country-specific billing regulations that apply to electronic invoicing, and those rules vary widely.
• Not every country requires a government tax authority to approve an invoice before it’s paid.
• The scenario that actually disrupts legal ops teams usually isn’t a government rejecting an invoice. It’s the reverse: a government has already cleared an invoice, and legal or the client then needs to adjust or reject it, and that resubmission is often more painstaking than a normal one.
• France, Italy, Germany, and Mexico are the examples that come up most often in the past , but the specific formats, rules, and consequences of a rejection differ by country and don’t generalize from one to the next, even inside the EU, which is still working toward a standardized approach.
• Many legal teams use a pro-forma invoice step to align with law firms before a firm submits the invoice to a government portal.
• Compliance responsibility doesn’t sit in one place: AP and Finance typically own compliance and payment, the firm owns tax authority submission and clearance, and legal ops’ role is keeping billing guidelines and process intact without adding delay.
• Collaborati data shows that non-U.S. invoice volume moving through eBilling platforms has grown sharply. Some countries saw more than 200% growth in invoice volume between 2024 and 2025, and that trend is expected to continue as more countries roll out similar requirements.

That’s how Cal Yelderman, Mitratech’s Senior Product Manager for TeamConnect, described the shift in a recent webinar. Where that step exists, the bigger risk usually isn’t a government rejecting an invoice outright. It’s the reverse: a government has already cleared something, and then legal or the client needs to unwind it.

A quick note on scope: Mitratech isn’t a tax expert; our focus is the e-billing workflow. This article draws on patterns we’ve observed working with legal ops teams and outside counsel across many countries, plus complementary materials from our product and services teams. It is not tax or legal advice. Requirements vary by country, change frequently, and often include exceptions this piece doesn’t cover, so please confirm specifics with qualified tax counsel before relying on anything here.

What Is International eBilling Compliance?

There’s no single definition, since requirements are set country by country. Clearing an invoice with a government tax authority before payment (sometimes called a continuous transaction controls, or CTC, model) is part of it in France, Italy, and Mexico. It isn’t how compliance works in Germany or the UK, where the requirements look different; both countries are tightening their own e-invoicing rules without adopting that clearance step, yet.

If there’s a common thread, it’s this: understanding whatever region- and country-specific billing regulations apply to electronic invoicing where you’re billing. That’s deliberately broad, because a narrower definition stops holding up once you look at more than two or three countries.

It’s also worth remembering this isn’t a legal-billing-specific rule. Where a government e-invoicing portal requirement exists, it typically applies to all billing in that country, not just outside counsel invoices. Legal billing just tends to be more complicated to fit into it, because of matter coding, billing guidelines, and the back-and-forth review a legal invoice goes through before anyone agrees it’s correct.

Why the Rules Differ From Country to Country

Even inside the EU, which is working toward a more standardized approach through its VAT in the Digital Age initiative, individual member states are still at different stages, and what counts as a legally valid electronic invoice varies country to country. Some require a specific structured format, some accept a PDF, and some accept an industry format like LEDES without requiring it. None of that generalizes cleanly.
Cross-border legal billing wasn’t simple before any of this, either. It has involved tax compliance and multi-currency complexity for a long time, particularly across APAC. Singapore is one example: its conditional GST and withholding tax rules depend on where the work was performed, whether the billed entity sits outside Singapore, and even the currency of the invoice. That kind of complexity predates government clearance portals by years.

What’s actually new is the expanded scope of eInvoicing regulations that includes a government review step inserted earlier in the process, before payment rather than after. Where that applies, it disrupts the workflow for both the firm and the legal department, because the sequencing itself now has to be actively managed, not just the invoice content.

Here’s the shift in one view:

The Problem Usually Isn’t Government Rejection

It’s tempting to assume the main risk is a government rejecting an invoice outright. In practice, the scenario that causes the most disruption is usually the opposite: a government portal has already reviewed and cleared an invoice, and legal ops or the client then decides it needs to be adjusted or rejected, for a billing-guideline reason, not a tax reason. “Payment delays stretch further if the government approves something and the legal team then kicks it back, since resubmission can be more painstaking than a normal resubmission…” Cal said on the same webinar.

That’s the real reason a pro-forma invoice step exists: it gives legal ops a chance to catch a billing-guideline problem, an out-of-town expense that shouldn’t have been billed, paralegal work billed at partner rates, before a firm submits anything to a government portal, instead of after.

How the Pro-Forma Invoice Workflow Works

As Cal explained it: “The pro forma invoice is about getting alignment between the legal team and the firm before submitting to the government.” The firm will have to make updates and resubmit until there is alignment on amounts, matter coding, and billing-guideline compliance. Only after that does the firm submit to the actual government portal, which typically wants far less line-item detail than the legal invoice does. Once cleared, the firm brings the approval file or reference ID back, that gets attached to the original invoice, and it moves to AP.

This is a pattern, not a universal legal requirement. Different vendors and tax authorities describe the underlying transaction models differently, and there’s no single agreed-upon way to categorize them yet.

Where International Invoices Commonly Go Wrong

A missing tax authority reference ID, or an invoice submitted without required jurisdiction information, is a common source of rework and delay, and in some cases, rejection. Some government portals also assign their own invoice number or invoice date that doesn’t match the firm’s original invoice, which is why accounts payable teams need visibility into both records to reconcile what they’re paying against what legal ops actually approved. Whether an invoice needs a specific structured format rather than a PDF is a country-by-country question, and clients have described real internal confusion about whether that’s a government requirement or just how their process has always worked.

A few other ways things can go wrong include:

• Not including the tax team or finance early on in the process
• Being reactive instead of proactive
• Not communicating the purpose/value/needs of corporate legal invoicing processes

How TeamConnect Supports International eBilling Compliance

This is the part we can speak to with more confidence, since it’s our product and not someone else’s regulation. TeamConnect is built as a configurable platform rather than one encoding a single country’s rules, with country-by-country configuration layered on by your team or by our professional services group. Available today on TeamConnect version 8, that includes pro-forma invoicing, approval holds, and key tax authority details like the Tax Authority Reference ID, tax jurisdiction, alternate invoice number, and alternate invoice date, built to map onto whatever your specific countries call them. Every country has its own name for the approval ID (it might be the KPID in Korea, or the AOID in Australia), and rather than build a separate field for each one, the same universal field gets configured per country. When a firm updates a tax authority field or attaches approval documentation in Collaborati, it syncs automatically and notifies the right internal group. Automating the process is easy with options to configure rules that auto-release the approval hold once that data is populated.

A common question we hear asks whether there is an automated validation of the invoice total between the attached government clearance file and the TeamConnect invoice. No, out of the box, that reconciliation is manual, but TeamConnect custom rules could be built for this. Reconciling invoices is an area of ongoing discussion. Professional services have helped some clients automate parts of it, but it’s worth knowing where that line currently sits.

Operating on older systems some clients explained that firms were using email to confirm alignment, which carries its own cost. As Cal put it: “There’s security risk, there’s a lack of information, and there’s time your attorneys spend reviewing something over email, versus going through the system with the automation and validations you already have in place.”

Get a closer look at Mitratech Teamconnect for International eBilling Compliance in our free one-pager. Or, schedule some time with our team of experts.

Why International Invoice Volume Keeps Growing

Non-U.S. invoice volume moving through eBilling platforms has grown sharply. “From 2024 to 2025 we saw a big jump in non-U.S. invoices approved, with some countries seeing better than a 200% increase in invoice volume and net invoice total,” Cal noted on the webinar. Not every legal department bills heavily in every country adding these requirements, so the practical approach is prioritizing the biggest friction points and highest volumes first, then building out from there as more countries roll out their own versions over the next several years.

As Cal put it, closing out a recent client session on this topic: “International tax compliance isn’t the most fun topic to talk about, but it’s an important one, and one we’re here to work with you on.”