
This is part 3 of our series on Pay-as-you-go pricing:
Introducing PAYG and why it's a popular choice for fast moving companies
Scaling PAYG pricing and advanced considerations (this article)
TL; DR PAYG is simple to launch, but running it at scale requires safeguards, predictable enterprise controls, and a careful approach to evolving meters and pricing.
Pay-as-you-go (PAYG) pricing is appealing because of how straightforward it is. You choose a unit, set a rate, meter usage, and charge customers based on what they consume. It’s easy to launch, simple to communicate, and fits naturally with how many modern products deliver value. PAYG is just one of several SaaS pricing models, including subscription, usage-based, tiered, freemium, per-user, and flat-rate models. SaaS pricing strategies vary widely, allowing companies to tailor their approach to optimize revenue and customer satisfaction.
Once you’re live with PAYG, new challenges emerge. Usage is unpredictable. Customers behave in unintentional ways. Larger buyers need predictability and budget controls. And as your product grows, your metering and pricing have to grow with it, without breaking existing customers or creating a maze of exceptions.
This article covers the advanced side of PAYG:
Protecting your budget and your customers
Making PAYG enterprise-ready
Evolving your pricing and metering safely over time
We’ll also touch on how different pricing strategies can be adapted as products and customer needs evolve. These are the lessons most companies learn the hard way.
Good usage-based pricing depends on trust. Customers want to feel confident that their bill reflects the value they received, not a mistake, misconfiguration, or runaway workflow they didn’t intend to trigger. And you want protection from usage patterns that can blow up infrastructure costs or create difficult billing conversations.
Not all usage is intentional. Sometimes it’s the result of:
Bots hitting a public API endpoint
A script or queue system retries aggressively
Customers misunderstanding how often a job should trigger
A background job keeps running even after a user thinks they’ve stopped it
It’s helpful to think of anomaly detection less as a fraud system and more as a safety net. Even simple rules—“alert if usage grows 4× faster than normal”—go a long way toward preventing surprises.
One of the best ways to build trust is to give customers clear boundaries:
Soft caps notify them when they’re approaching a limit and let them choose whether to continue
Hard caps cutoff service to stop runaway spend entirely
Throttling reduces volume without cutting off service
Many companies discover these features only after a difficult billing conversation. Adding them early creates stability for both your customer and your product.
Usage-based pricing feels fair when customers understand what’s happening. Helpful tools include:
Usage alerts at key thresholds
Daily or weekly usage summaries
Mid-cycle invoice previews
“At your current pace, expect to pay about $X” forecasts
These small touches help prevent the fear that a surprise is waiting at the end of the month.
PAYG often starts in a PLG environment, but it can absolutely support enterprise selling. Larger buyers just care about a different set of needs: predictability, control, and the ability to plan budgets confidently.
Enterprise procurement teams usually want:
A clear sense of the highest possible bill
Pre-approved spending limits
Consistent line items they can allocate internally
Controls that prevent unexpected usage from different departments
None of these requirements are incompatible with PAYG—you just need mechanisms like minimum commits, usage caps, and reliable usage reporting.
As you start working with bigger customers, you’ll eventually negotiate:
Custom rates
Region-specific pricing
Legacy customer grandfathering
Migration plans for older contracts
A common mistake is hard-coding these exceptions, or duplicating plans until every enterprise customer sits on their own one-off version.
A healthier pattern is:
Maintain a single canonical version of your pricing
Add customer-specific overrides in a controlled way
Keep a clean version history of changes
Create a process for migrating customers safely
This preserves flexibility without creating long-term chaos.
For customers who need budget certainty, it’s common to introduce:
A minimum monthly charge
An annual commit that includes a certain amount of usage
Hard limits that require customer approval to raise
Overages are still billed at your standard PAYG rate, but the commit provides predictable revenue and a stable internal budget for the buyer. This is often the first step in moving from pure PLG toward more traditional enterprise contracts.
The early days of PAYG are simple: one meter, one rate. As your product grows, this simplicity can become harder to maintain. New features require new meters, teams begin instrumenting usage independently, and pricing changes accumulate faster than expected.
As different parts of the product evolve, new meters naturally appear. Without some structure, you end up with:
Multiple meters that represent the same concept
Meters with inconsistent or unclear units
Features that generate usage but aren’t included in pricing
Customers missing certain meters because they were added mid-cycle
None of this breaks your billing directly, but it does erode clarity, which makes pricing harder to reason about and explain.
When you modify a rate or change how a unit is defined, the effects ripple outward:
Existing customers may be on older pricing
Contracts may reference specific units or thresholds
Historical usage may no longer align with the current pricing
Your team may lose the ability to compare usage over time
Avoiding these pitfalls requires versioning both meters and plans, and having a migration path that doesn’t force customers into mid-cycle disruptions.
Even when the unit stays the same, pricing adjustments can make historical analysis messy. If you lower a price, customers expect older invoices to remain stable. If you raise a price, you need clear communication and often phased transitions.
Treating meter definitions as durable contracts, rather than casual engineering details, helps ensure that changes don’t break downstream systems, expectations, or analytics.
Calculating usage times a rate is the easy part. The harder work is everything around it:
Detecting unusual patterns
Updating pricing safely
Managing exceptions
Communicating usage clearly
Enforcing caps and limits
Keeping multiple teams aligned
Preserving backwards compatibility
This is the sort of hidden operational complexity that grows slowly until it becomes a major drag on engineering time.
It’s also the reason platforms like Schematic exist. Not to change your pricing strategy, but to handle the messy parts so you don't have to.
"Our goal is to push all of this [billing] state management onto [Schematic] and not have to model anything locally." Peter Keens, Engineering @ Appy.ai
PAYG works beautifully when your value maps to activity. But keeping it healthy at scale requires more than a rate and a meter. It requires guardrails, a way to support enterprise expectations, and a thoughtful approach to evolving meters and pricing over time.
The teams that do PAYG well aren’t the ones with the simplest pricing—they’re the ones with the clearest processes, the strongest protections, and the confidence to adapt their pricing without breaking trust.