If you're building a SaaS platform, you're not just solving problems—you’re creating ecosystems. But here’s the catch: the more features your users need to outsource, the more likely they are to outgrow your product. One of the easiest features to bring in-house? Invoicing.

Offering invoicing directly in your platform doesn’t just make life easier for your users—it turns your software into a one-stop shop. It boosts retention, opens up new revenue streams, and helps you stay competitive in a saturated market.

Here’s how to do it fast and effectively:

Why Do You Need an Invoicing API?

Benefits For Your Platform

What Are Risks?

Cost Of Integrating Invoicing Feature

Compare To Other Invoicing API’s

Space Invoices Is Here To Scale With You

 

 

Why Do You Need an Invoicing API?

No matter what niche your SaaS platform serves, one thing is universal—every business needs to invoice. And yet, most still do it manually, especially SMBs. That means wasting time, spending money on paper, or even digital tools that require a human to create and send each invoice. Not to mention, manual invoices take longer to get paid, and whoever is handling them needs to stay up to date with ever-changing invoicing regulations. And since humans aren’t perfect, mistakes happen—which means more time fixing issues and potential fines, leading to even more lost money.

This is exactly why governments around the world are starting to mandate e-invoicing. For them, it allows real-time reporting and reduces tax fraud. For businesses, it means saving money, streamlining the process, and eliminating errors.

But for platforms like yours, e-invoicing goes beyond internal efficiency. You already offer niche services to a specific audience, and competition is everywhere. While it’s tempting to throw in more features to become a one-stop shop, that only works if the features are actually useful and simple to use.

And that’s where invoicing fits perfectly. Your clients already need it, they’re already using your platform, and it’s cheaper and easier for them than building or integrating their own invoicing solution.

By offering invoicing, your platform becomes more attractive to new clients, helping you reduce acquisition costs. It also makes existing clients more loyal, since they can now handle even more of their business in one place.

And perhaps the biggest benefit? You can monetize it. Here are three proven ways:

Usage-Based Only – Clients pay only for what they use. It’s flexible and user-friendly, but offers unpredictable revenue.

Hybrid: Subscription + Usage-Based – Clients pay a monthly subscription to unlock the feature with some included benefits, then pay for additional usage. It strikes a balance between flexibility and revenue predictability.

Flat Subscription – Clients pay a fixed monthly fee for unlimited usage. It gives you predictable recurring income, though it may be less appealing to clients who invoice infrequently.

 

 

What Are the Risks?

Risk is always part of the equation, especially when it comes to integrating a fresh solution like e-invoicing. It’s a relatively young market, and that alone can make the decision feel heavier. But at Space Invoices, we specialize in working with companies that face exactly this kind of uncertainty—and our goal is to remove as much of that risk as possible.

Here are the main risk factors when it comes to choosing the right invoicing API—and how we’ve built around them to make your life easier:

Compatibility – The API needs to fit smoothly into your software stack. That’s why we offer detailed documentation, based on years of hands-on API experience, and a freemium model so you can test it first, followed by transparent, usage-based pricing to help you grow at your own pace.

Credibility – With invoicing APIs still being a relatively new space, a lot of providers have no real testing history, yet charge high fees. We’ve spent years developing, refining, and collecting a strong line-up of case studies, certifications and social history, to back our reliability.

Support – One of the best indicators of a quality API provider is how quickly and thoroughly their team responds. We’re known for being accessible, responsive, and helpful—and in most cases, our partners are fully integrated in under a week.

Features – Not every API is built for scale. You need multitenancy and white-labelling to sell invoicing to your clients, a broad country list to ensure global compliance, and cross-border capabilities to future-proof your expansion. Our API includes all of that—so you won’t need to switch providers when you grow.

We’re confident that we’ve covered all the critical bases—but beyond the product, we’re here to collaborate, stay flexible, and jump on a call with you anytime to figure out what works best. At the end of the day, our job is to help you integrate the invoicing feature for your needs.

 

 

Cost Of Integrating Invoicing Feature

There’s a common debate when it comes to adding invoicing to your platform: build it in-house or integrate a third-party API.

Building your own invoicing feature gives you complete control—it’s tailor-made to fit your platform, you keep 100% of the profit, and you’re not dependent on anyone else. Sounds ideal, right? But here’s the catch: to make it worth the investment, you need to be a large company, serving hundreds or thousands of clients, and processing millions of invoices per month.

The reality is, building an invoicing API takes well over a year of development, with multiple developers’ salaries, constant maintenance, and ongoing compliance updates for every country you operate in. Just to give you an idea—getting certified in Portugal alone can take more than a year, and the regulations keep evolving.

That’s why most businesses choose to integrate a third-party API. It’s significantly cheaper, can be up and running in days, and with the right provider, it can feel like it was built into your platform from day one—all without the stress, cost, or never-ending upkeep.

 

 

Compare To Other Invoicing API’s

Of course, Space Invoices isn’t the only API out there that can help you integrate invoicing. But we genuinely believe we’re the best fit for SMBs. Still, the choice is yours. And since we know you’ll compare options (as you should), we’ve written honest comparison guides—because we’re here for long-term partnerships. Here’s how we stack up against other commonly considered providers:

Monite vs. Space Invoices: Monite offers advanced financial automation, which is great for enterprise finance teams. But Space Invoices gives you global compliance in 70+ countries, with a faster setup, lower costs, and an API tailored for platforms looking to launch invoicing quickly, upsell clients, and grow revenue from day one.

Stripe vs. Space Invoices: Stripe is ideal for e-commerce payments, but not built for platforms wanting to resell invoicing features. With Space Invoices, you get full white-labelling, faster integration, and more control over margins.

Fonoa vs. Space Invoices: Fonoa is designed for large enterprises with complex tax automation needs. Space Invoices, on the other hand, is built for SaaS and fintech companies that want to move fast, expand globally, and offer compliant, white-labelled invoicing at a more affordable price point.

 

 

Space Invoices Is Here To Scale With You

If you are trying to enhance your platform’s one-stop shop position, the Space Invoices API is here for you. With us, you can:

Use one API for current and future global tax and invoicing compliance.

Support and upsell your clients worldwide, creating a new revenue stream.

Ensure all invoices are archived and successfully reported to regulatory institutions.

Become a one-stop shop for current and future clients.

Streamline processes and eliminate manual errors, saving both time and money.

Have questions about invoicing features for your app?

We’re ready to help.

Additional reading:

• 2030 Intra Community E-invoicing Mandatory EU ViDA
• 3 Best White-Label Invoicing APIs for B2B SaaS, Fintech, and Neobank Platforms
• Ask Your Developer: Key Insights for the Build vs Buy Debate in Invoicing API