E-invoicing, buy finished software or build your own?

The honest answer first, for the large majority of firms a finished program is the right call. Building your own software for e-invoicing alone pays off in a few cases, and those can be named.

Why finished is usually enough

E-invoicing is a standard, not a competitive edge. The formats are the same for everyone, and a maintained product keeps them current when rules change. That is the argument against building. You would rebuild something the market already offers well and cheaply, and then have to maintain it yourself.

When a custom workflow is cheaper

There is a clear point where building your own pays. When you process many invoices a month, already run your own systems, and your process differs from what finished products assume. Then the answer is often not a large program but a small connection that ties the finished tool to what you already have.

The three-year sum

Count honestly. A subscription costs every month, and over three years that adds up. A custom solution costs once to build and then to maintain. Only when the running licence cost clearly exceeds the sum of building and maintaining is building the cheaper choice. For most small firms that point is not reached.

The most common right answer

In practice the answer is often mixed. A finished program for e-invoicing, plus a small connection to what you already run, such as filing into SharePoint automatically. You buy the standard and build only the one piece that is genuinely yours.