E-invoicing can often seem to be the bane of an SME’s existence. As more large companies begin to demand that their SME suppliers use this or that platform to deliver electronic invoices, the hassle can easily seem much greater than the potential value for the supplier. Even as access becomes simpler, the need to manage various solutions for various buyers can be onerous.

Small companies are starting to have access to solutions geared specifically to their needs, which does add to the value proposition somewhat. A number of new vendors are focusing specifically on the SME space to help make it a little bit easier for small companies to migrate to e-invoicing. American Express, for example, offers AcceptPay—a dedicated SME e-invoicing solution.

Plus, Tradeshift—which launched last May—holds some promise of radically changing the landscape for e-invoicing in general and SME invoicing in particular. The company launched first in the SME space, offering a simple online portal for companies to manage, store, and send e-invoices to their counterparties. And get this, it is free.

Companies, sick of the relatively-high per-invoice charge that often comes with other e-invoicing solutions, have begun to take notice. The company has been highlighted in a number of publications and tech blogs as a potentially disruptive technology longer-term. It has since launched a free e-invoicing solution for large companies, as well.

But even with more dedicated SME vendors, the big problem that plagues the e-invoicing market still remains. Interoperability.

Zilvinas Bareisis, Senior Analyst at Celent, notes in a recent report that without the common standards, a supplier may be forced to join multiple such e-invoicing providers, something they are reluctant to do.

The market will not reach maturity until there is a deeper migration away from closed three-party models (supplier, buyer, e-invoicing vendor) to more open four-party e-invoicing network exchange models (supplier, buyer, e-invoicing vendor, network of other e-invoicing vendors connected to other buyers and suppliers), according to Bareisis.

This is slowly happening as some vendors work on interoperability with each other, but it is a sluggish and difficult process as vendors must link up tech platforms, and also harmonize commercial agreements, service levels, pricing, and so on.

Nonetheless moving to this approach is essential for e-invoicing to develop further and become a standard tool for B2B invoice interactions, according to Bareisis: “Four-party models and interoperable networks of service providers are likely to prevail over the closed three-party e-invoicing solutions.”

Until such time as the fragmented market sees some cohesion, e-invoicing will continue to just be another sometimes-useful, sometimes frustrating tool that small companies must manage in order to interact with their larger corporate clients.