Should You Build or Buy Your SMS Solution? What SaaS Leaders Need to Know

Here’s a question popping up in a lot of product roadmap conversations right now: Should we build SMS into our platform, or do we buy it from a partner?

It sounds like a straightforward engineering call. It isn’t. Most teams that go the “build” route don’t find out how expensive that decision can be until they’re already six months in, by which point “maybe we should have bought” is not exactly a useful insight.

We sat down with TextUs CEO Martin Payne to get into what’s actually driving SMS adoption across SaaS right now, what building in-house really costs, and how to think through the decision before you make it.

SMS Is Table Stakes Now. Here’s Why.

Five years ago, SMS in a SaaS product was a differentiator. Today, it’s more expected—and the shift is happening across small, mid-market, and enterprise software alike.

Two things are driving it. Email has gotten so crowded that it’s genuinely hard to break through. And mobile-first communication has become universal—not just for younger users but across demographics. TextUs’s own research shows that Gen X and baby boomer audiences are just as receptive to SMS once they’ve opted in. This isn’t a generational trend; it’s a behavior shift across the board.

If your platform touches customer engagement, retention, or outreach in any meaningful way, SMS probably belongs somewhere in the picture. The real question is about who builds it.

What “Build” Actually Costs

We get the instinct to ask the question: How hard can this be? But the answer is: Harder than it looks, and more expensive than most teams budget for.

Unlike email, SMS falls under the Telephone Consumer Protection Act (TCPA)—enforced by the FCC—and carriers layer their own acceptable-use policies on top of that. 10DLC registration, opt-out threshold monitoring, and message-level compliance all require real, ongoing engineering attention. It doesn’t get built once and then forgotten.

“If you’re looking at doing anything remotely interesting from a functionality standpoint,” Payne said, “you’re looking at least a couple of engineers full time per year … up towards $300 to $500k.”

That’s before factoring in the 9-12 months it typically takes just to reach a first version. Add a channel like WhatsApp at scale, and the number climbs further.

The opportunity cost is the part teams underestimate most. Every engineering cycle spent on SMS infrastructure is a cycle not spent on the thing that actually differentiates your product.

What “Buy” Actually Looks Like

Buying SMS isn’t a simple decision; it’s a choice between a few different models depending on what your product needs.

TextUs’s white label customers generally take one of three paths:

• API access for teams that mainly need carrier operations handled without a full UI
• Embedded messenger, an iframe that lives inside existing software and syncs back to contact records automatically
• Full white label, a completed rebranded product best suited for campaign-driven use cases like sequences and keyword automations.

Payne’s framing is useful here: “People don’t build their own payment gateways anymore. They go with Stripe because it’s high-quality, reliable, and just easy.” The same logic is starting to apply to messaging infrastructure—and for most SaaS teams, the “build verses buy” math looks a lot like it does with payments once you run it honestly.

The Question That Makes the Decision

For product leaders trying to make the call, one question cuts through most of the noise: Is SMS part of your core differentiator, or is it something adjacent that supports it?

If it’s core—if SMS is the reason customers choose your product over a competitor—build it. Own it. The investment makes sense.

If it’s adjacent—if SMS is infrastructure that makes your core product stickier but isn’t the product itself—buying wins, every time.

From there, it’s a matter of realistic team bandwidth, honest time-to-market estimates, and what else that engineering budget could be doing instead.

Want the full framework for making this call? The Build vs. Buy Decision Analysis Guide gives you a side-by-side look at both paths. Want more firsthand knowledge from our CEO, Martin Payne? This video podcast goes even deeper (and no, you don’t have to fill out a form to watch it).

Or if you’re ready to talk through what the right model looks like for your product, explore TextUs’s white label solutions.

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