Key challenges of implementing e-invoicing

E-invoicing is spreading rapidly as governments push for greater tax transparency and companies seek efficiency gains. While the benefits are clear – cost savings, faster payments, and compliance – implementation comes with hurdles. From technical integration to differing national rules, businesses must address these challenges early to turn e-invoicing into an advantage rather than a burden.

How the e-invoicing landscape differs across Europe

• Poland: Poland is preparing for the National e-Invoicing System (KSeF), which will become mandatory in 2026. Companies will be required to issue invoices in a standardised XML format (FA(3)) and transmit them directly through the government platform.
• France: E-invoicing has been mandatory for B2G transactions in France since January 2020. The country is now moving toward mandatory B2B e-invoicing and e-reporting between 2026 and 2027. Invoices will be exchanged via certified Approved Platforms (PAs, previously known as PDPs) connected to the central Public Invoicing Portal (PPF). Companies will need to work with structured formats such as Factur-X, UBL, or CII to remain compliant.
• DACH Region: In Germany, all businesses must be able to receive structured e-invoices from 2025, with issuance obligations following in 2028. The invoices exchanged have to be aligned with the European EN 16931 norm. Austria and Switzerland follow similar approaches, especially in B2G invoicing.
• Benelux: Belgium has already introduced mandatory e-invoicing for B2G transactions and plans to extend the obligation to B2B invoices from 2026, building on its strong reliance on the Peppol network. The Netherlands and Luxembourg already mandate e-invoicing in public procurement, encouraging private-sector adoption as well.
• UK: The UK doesn’t currently mandate B2B or B2G e-invoicing, with the exception of the healthcare sector, where e-invoicing to the National Health Service (NHS) via Peppol is required. Accepted formats include both structured XML and unstructured PDFs, as well as traditional EDI standards such as UN/EDIFACT, EANCOM, and ODETTE.

Key e-invoicing challenges

1. Data integration and system interoperability

One of the biggest hurdles in e-invoicing is aligning new requirements with existing IT systems. Many companies still rely on legacy ERP or accounting software that was never designed to handle structured invoice formats like XML or UBL. As a result, integration often becomes a costly and time-consuming exercise, leading to data silos and inconsistencies.

The solution: Using an external e-invoicing system helps bridge the gap between old and new technologies. Such platforms can automatically convert invoice formats, harmonise data fields, and ensure compatibility across partners, reducing complexity and speeding up integration.

2. Data security and privacy

Invoices contain sensitive financial information, making data security and privacy critical concerns. The risks grow when multiple stakeholders and systems are involved, especially across different geographies with varying regulations. On top of cyber threats, companies must also comply with strict data protection laws such as the EU’s GDPR, California’s CCPA, and similar frameworks worldwide. Without robust safeguards, both compliance and trust in the invoicing process are at risk.

The solution: Adopting strong security measures, such as digital signatures, encryption, and secure transmission channels, is essential. Certified service providers can automate authentication and authorisation, ensuring ongoing compliance while reducing the risk of fraud and data breaches.

3. Compliance with diverse national regulations

Each country sets its own rules regarding e-invoicing formats, submission channels, and deadlines, which creates complexity for multinational companies. For example, invoices in Poland will be required to be issued in a structured XML format and transmitted through the national KSeF system. France, on the other hand, is rolling out a model where invoices flow through certified Approved Platforms (PAs) linked to a central portal. To make matters more complex, these regulations evolve frequently, requiring companies to stay up to date across all jurisdictions where they operate.

The solution: Partnering with providers that continuously monitor regulatory changes and automatically update systems ensures invoices remain compliant. This proactive approach minimises the risk of errors, delays, and fines.

4. Real-time reporting and CTC models

A growing number of countries are moving toward Continuous Transaction Controls (CTC), where invoices must be reported to tax authorities in real time or near real time. This shift transforms invoicing from a back-office process into a compliance-critical activity that directly affects cash flow. Any failure in reporting can result in rejected invoices, delayed payments, or even fines.

The solution: The best way to cope is through automation: pre-validating invoices before submission, integrating directly via APIs, and setting up monitoring dashboards to track statuses in real time. This ensures compliance while reducing the risk of operational disruption.

5. Error handling and business continuity

E-invoicing introduces a new dependency: government platforms. If a system like Poland’s KSeF or France’s PPF goes down, businesses may be unable to issue invoices, which in turn delays payments and impacts cash flow. Additionally, errors such as invalid XML structures or missing fields can lead to rejected invoices, forcing companies to rework and resubmit them.

The solution: Companies should implement automated pre-validation tools that check invoice data before submission. It’s also essential to set up fallback procedures, such as offline modes or queuing systems that resend invoices once the platform becomes available again. By planning for downtime and errors in advance, businesses ensure continuity and minimise disruptions in their financial operations.

6. Change management and user adoption

Even the most advanced e-invoicing solution will fail if employees and finance teams are not ready to use it. Resistance to change is common, especially when new processes replace long-standing practices such as issuing invoices in PDF or paper form. Without proper preparation, the transition can lead to errors, delays, and frustration across departments.

The solution: Organisations should treat e-invoicing as a change management project rather than just an IT rollout. Clear communication about the benefits, hands-on training, and phased implementation can build user confidence. With the right approach, employees become advocates for the new system rather than obstacles to its success.

7. Interdepartmental coordination

For international companies, one of the less obvious but equally critical challenges of e-invoicing lies in aligning different departments. IT, finance, and operations each have their own priorities, workflows, and systems, which can make coordination difficult. Diverse objectives, incompatible ERP systems, and varying levels of readiness can slow down implementation. On top of that, regulatory compliance across multiple regions requires departments to work closely together, while tailored training is needed to ensure employees understand their specific roles in the new process.

The solution: Successful adoption depends on breaking down silos through clear communication and coordinated workflows. Companies should involve representatives from all key departments early in the project, define shared objectives, and ensure system compatibility across functions. Providing role-specific training and setting up cross-departmental governance structures helps align efforts, ensuring smoother implementation and more efficient operation.

8. Challenges of implementing Peppol

While Peppol is an elegant solution for interoperability, its implementation can be demanding. Countries often extend the model with local clearance or CTC requirements, which adds regulatory complexity. So for businesses, the challenge is understanding how the local CTC requirements interact with the Peppol standard. Also, if the company has an outdated or highly customised system, integrating ERP systems with a Peppol Access Point can be time-consuming. Moreover, poor master data, such as incorrect VAT numbers or product codes, may result in invoice rejections. In addition, in markets where Peppol is not mandatory, uneven adoption can force businesses to maintain parallel invoicing processes, limiting the expected efficiency gains.

The solution: Working with a certified Access Point, such as Comarch, minimises these risks. Providers take care of local compliance, technical integration, data quality, and partner onboarding, helping companies benefit from Peppol while ensuring smooth and secure operations.

9. Cost and resource constraints

Transitioning to e-invoicing often requires significant upfront investment in IT systems, staff training, and process redesign. For many organisations – especially small and medium-sized enterprises – these costs can seem prohibitive. Add to this the uncertainty around future regulatory changes, and it’s easy to see why some businesses delay their projects until the last possible moment.

The solution: While the initial cost of an e-invoicing system is high, it typically pays off quickly. Research shows that digital invoicing can reduce processing costs by 50–60%, saving several dollars per invoice processed. However, it can still be reduced by adopting cloud-based e-invoicing solutions in a Software-as-a-Service (SaaS) model. These platforms spread costs over time, scale with the business, and remove the need for heavy infrastructure investments.

10. Scalability across multiple markets

For multinational companies, e-invoicing rarely stops at one border. Expanding operations into new markets often means dealing with a patchwork of standards, formats, and legal frameworks. For example, an invoice format valid in Germany won’t necessarily meet requirements in France or Poland. Managing separate solutions for each country quickly becomes unsustainable.

The solution: Centralising compliance through a global e-invoicing hub. Such platforms support multiple formats and automatically adapt to local requirements, whether that’s XRechnung in Germany, FA(3) XML in Poland, or Factur-X in France. This not only simplifies international operations but also ensures that companies can scale their invoicing processes in step with business growth.

Mitigating the risks of e-invoicing
Adapting to change is never easy – especially when it touches fiscal regulations and the day-to-day operations of international businesses. Managing global e-invoicing challenges such as regulatory diversity, system integration, data security, and coordination across departments requires careful planning and specialised tools. Done right, the transition ensures compliance while streamlining processes and supporting broader business objectives.

Comarch E-Invoicing was built to address these challenges head-on. The platform combines scalability and flexibility to handle increasing transaction volumes, while seamlessly integrating with existing IT environments. This reduces security risks, simplifies compliance, and improves collaboration across business functions.

Discover how Comarch E-Invoicing can help your company minimise risks and unlock the full benefits of electronic invoicing. Our experts are here to guide you through every step of the transition.