SaaS revenue models and billing models explained

“Revenue model”, “pricing model” and “billing model” are used as if they meant the same thing. They do not. Most articles on SaaS revenue models list pricing structures and call them billing models, or describe a billing cycle and call it a revenue model. Treating the three as one leads to decisions that look fine on a pricing page and fall apart in finance, support or the payment system.

This guide separates the three layers and then follows the consequences into your operations: how billing timing changes your cash, what happens at a mid-cycle change, how free trials interact with billing dates, why monthly and annual billing behave differently, and what a failed payment means under each model. It uses worked examples with the arithmetic shown, and every rule or statistic names where it comes from. Where the common advice has no traceable source, we leave it out and say so.

For the structure of the charge itself, see our guide to SaaS pricing models.

Revenue model, pricing model and billing model

A company can change one layer without changing the others. Each change has different effects on customers and on your systems, so it helps to know which one you are making.

A worked example: one company changes each layer in turn

Take a fictional company, Acme Notes, selling to teams. All details are illustrative.

The same company made three different decisions, each with different consequences. A pricing page edit can hide a billing change, and a billing change can quietly alter your churn.

The main SaaS revenue models

Subscription. Customers pay on a schedule, usually monthly or annually, for continued access. Revenue is recurring and easier to forecast, but it depends on customers renewing. Every renewal is a point where a customer can choose to leave or a payment can fail.

Usage-based. Customers pay according to what they use. Revenue grows as customers use more, and customers can start small. The trade-off is that revenue and bills vary from month to month. Usage-based billing needs a metering step, so accurate measurement becomes part of the product. Read more about usage-based billing.

Hybrid. A subscription base with usage on top, or seats plus usage. It gives you predictable revenue that still grows with use, and it combines the demands of both models.

Prepaid. Customers buy credit or a balance in advance and draw it down. Cash arrives first and customers control their spend, but the balance has to be tracked accurately. Stripe’s documentation describes this as credit burndown, and now steers new usage integrations that need prepaid credits, commitments or ramp schedules to a dedicated tool.

Freemium to paid. A free plan that converts a share of users to paid plans. It is a way of acquiring customers, layered on top of one of the revenue models above.

Billing timing: in advance, in arrears and the options between

Billing timing decides when the invoice is issued relative to the service period. Zuora’s documentation defines it plainly: in advance means the invoice is issued before the period starts, and in arrears means after it ends. Its example is a quarterly charge for April to June: invoiced on 1 April in advance, or on 1 July in arrears.

Zuora also states two facts that matter when you plan a change. Billing in advance is its default. And billing timing is set when a subscription is created, not by amendment, so for existing products it recommends creating a new rate plan and moving customers to new subscriptions. Other systems differ, but the principle holds: a billing timing change is rarely a toggle.

Cash-flow arithmetic: what timing does to your cash

Take a customer who pays $100 a month, or $1,200 a year paid up front.

Under monthly billing in advance, a payment is collected at the start of each month, so by day 90 four payments have been collected and by day 330 all twelve. Annual billing front-loads the whole year on day 0. Neither is better in general: annual brings cash early and makes each renewal a single large decision, while monthly spreads risk across twelve payments.

Billing in arrears moves each payment back by one period. In the quarterly example above, the same $300 arrives on 1 July instead of 1 April: three months later, with the service already delivered.

Monthly or annual billing

Annual billing is often discussed as a pricing tip. It is a billing-model decision with specific effects.

• Cash. Annual billing collects a year of revenue at once, as the table above shows.

• When customers leave. Annual billing defers cancellations to the first renewal. Buffer’s analysis of its own subscribers (about 161,000 Stripe subscriptions, 2018) found that monthly subscribers cancelled most often around days 30 to 40, and that about 60% of the churned annual subscriptions cancelled between days 360 and 390. That is one company’s data, now several years old, so treat it as an illustration of the pattern: annual billing delays churn, it does not remove it.

• Failed payments. An annual renewal is a single payment. If it fails, the customer is at risk of losing access for a year’s worth of value. The failure is rarer but the stakes of each one are higher.

• Discounts. If you offer two months free on an annual plan, a customer pays $1,000 up front instead of $1,200 across the year. Decide whether the early cash is worth the lower revenue, and for which customers.

We did not use the widely quoted retention percentages for annual versus monthly plans. We found several, from publishers with a commercial interest and with no cited dataset or time window.

Mid-cycle changes: what billing has to work out

A customer who changes plan mid-cycle creates a proration problem. Stripe’s documentation has a clear example: upgrading from a $10 plan to a $20 plan halfway through a period bills an extra $5, made up of a $5 credit for the unused half of the old plan and a $10 charge for the new plan.

Four details from that documentation are worth knowing:

1. Proration applies to charges billed in advance. Usage-based billing is not prorated.

2. It is calculated to the second by default, and changing price, quantity or billing anchor triggers it.

3. It can be switched off, but the customer then pays the full new price on the next invoice.

4. Downgrade credits can surprise you. Negative prorations are not refunded automatically, and in Stripe’s worked example one billing mode produces a credit for time the customer never paid for, a net of minus $3.34, while another credits at the last price billed, a net of zero.

Every billing system has its own rules. The principle is the same: decide in advance what happens on an upgrade, a downgrade and a pause, and test each case.

Free trials and billing dates

A trial adds a date that your billing has to respect. Stripe’s documentation describes how a free trial behaves: a zero-dollar invoice is created at the start, a card is not required, and if no payment method is on file at the end of the trial the subscription can be cancelled, paused or invoiced, depending on settings. At the end of a trial the invoice is created and charged about an hour later. Usage during a trial is recorded but not billed.

Two questions to settle before you launch a trial:

• Card up front or not? Requiring a card lowers friction later and filters sign-ups. Not requiring one raises sign-ups and raises the share who never pay.

• What happens at the end? Decide whether the subscription starts, pauses or cancels, and make sure customers know in advance.

The stub period

Another date issue is the stub period. Suppose a customer signs up on 24 January and your billing cycle is anchored to the 1st of each month. The period from 24 to 31 January is a part-month. For a $100 plan it is 8 days out of 31, so $25.81 if prorated. Stripe’s documentation notes that a partial period before the first full invoice produces a prorated invoice, and that setting proration to none makes the stub period free. Choose deliberately, because an unprompted free week is still a decision.

Anchors have their own quirk. A subscription anchored on the 31st renews on the last day of shorter months.

What a failed payment means under each model

A failed payment is not the same event under each model. Here is how it differs.

What can be recovered

Not every failed payment is recoverable. Stripe’s documentation separates soft declines, which can be retried, from hard declines such as a stolen card or an incorrect number, which are not retried until a new payment method is supplied. Its Smart Retries are the default for new accounts, at up to eight retries over two weeks, and after the retries are exhausted the subscription can be cancelled, marked unpaid, left past due or paused. Retry policies are configurable and differ between systems.

How much churn comes from failed payments? Recurly’s July 2026 data reports median annual churn for SaaS of 3.22%, of which 2.16% is voluntary and 1.06% is involuntary, about a third. Involuntary churn falls as revenue per customer rises: 1.30% at a price of $10 to $25, 0.74% at $50 to $100 and 0.18% above $250. The page does not disclose its sample size and contradicts itself in places, so use it as a directional guide. It shows that failed payments hurt low-price plans most, and that the right fix depends on your price point.

We did not use claims that failed payments cause about half of all churn. They appear in industry write-ups with no clear source, and Recurly’s SaaS data does not support them for SaaS. For more on how to recover failed payments, read about involuntary churn, the SaaS dunning playbook and how dunning management works.

Usage billing: what an arrears invoice contains

Usage billing in arrears needs an invoice that the customer can follow. A well-built one has:

1. The base fee, if any, billed for the period.

2. Each metered item with the quantity used and the unit price.

3. Any allowance or credit applied, shown as a deduction.

4. Tax for the customer’s jurisdiction.

5. The total, with the period dates.

Disputes tend to come from the same places: the customer did not expect the number, the period or timing was unclear, or a line cannot be reproduced. Zuora’s glossary notes that customers may struggle to budget for an end-of-cycle bill. We found no reliable published data on usage-billing dispute rates, so we make no claim about how often they occur. The practical remedies are the ones the documentation points to: allowances, previews and clear invoices, and for some customers prepaid credits.

How to change a billing model: a checklist

Billing models change less often than pricing, and the change is harder. A checklist:

1. Check how your system sets timing. In some, billing timing is fixed when a subscription is created, so a change means new subscriptions.

2. Decide who moves and when. New customers only, or existing customers at renewal.

3. Preview invoices for a sample of customers.

4. Check proration, anchors and trials for the new model.

5. Plan for failed payments. An annual move concentrates risk in a single renewal; make sure retry and recovery rules are ready.

6. Tell customers what changes and when, in their own terms: the amount, the date and what they need to do.

7. Check with finance how the change affects the way revenue is reported.

8. Watch the first cycle: failed payments, support tickets, cancellations.

OpenByte bills subscription, usage-based and prepaid models, in advance or in arrears, in any currency, with local tax built in, and works out part-month charges, pauses, credits and refunds automatically. See recurring billing software for how it handles renewals.

Common mistakes

• Treating the three layers as one. A pricing change can quietly become a billing change, and nobody plans for it.

• Moving to annual billing without a renewal plan. Fewer payments means each failed one matters more.

• Usage billing without clear bills. Variable bills that customers cannot read turn into disputes.

• Forecasting revenue as if every payment succeeds. Failed payments and churn are part of the number.

• Treating a billing change as a toggle. In many systems it means new subscriptions and a migration.

• Ignoring the stub period. A free or prorated first week is a decision.

Statistics we did not use

• Retention rates for annual versus monthly plans from publishers with no cited data.

• Claims that failed payments cause a fixed share of all churn, where the source is unclear.

• Working-capital and customer-lifetime uplift figures from annual billing, seen only second-hand.

• Vendor-reported recovery totals, which are marketing figures.

Frequently asked questions

What is a SaaS revenue model?

How a business earns its money: subscription, usage-based, hybrid, prepaid or freemium to paid. It is different from the pricing model, which sets what is charged, and the billing model, which sets when and how it is collected.

What is the difference between a pricing model and a billing model?

A pricing model is what you charge and how it scales. A billing model is when and how you collect: monthly or annual, in advance or in arrears, with what trial rules.

What is the difference between billing in advance and billing in arrears?

In advance, the invoice is issued before the service period. In arrears it is issued after. In Zuora’s example, a quarterly charge for April to June is invoiced on 1 April in advance or on 1 July in arrears.

Can a company use more than one billing timing?

Yes. A common hybrid is a fixed fee billed in advance and usage or overage billed in arrears on the same customer.

Should I bill monthly or annually?

It depends on cash needs, customer preference and renewal risk. Annual brings cash early and defers cancellations to the renewal, but concentrates risk in one payment.

What happens when a customer upgrades mid-cycle?

For charges billed in advance, the system credits the unused part of the old plan and charges for the new one. In Stripe’s example an upgrade from $10 to $20 halfway through a period bills an extra $5. Usage-based charges are not prorated.

How do free trials interact with billing?

A trial adds a start date and an end date. At the end, the first invoice is created and the subscription starts, pauses or cancels depending on settings and whether a payment method is on file.

What happens when a recurring payment fails?

Soft declines can be retried, hard declines usually cannot until the customer supplies a new payment method. After retries are exhausted the subscription can be cancelled, marked unpaid or left past due, depending on your settings.

Key takeaways

• Revenue model, pricing model and billing model are three layers. Mixing them up is how good pricing pages turn into messy finance.

• When you bill changes your cash. Annual billing up front brings cash in sooner, while monthly billing is easier for customers to say yes to.

• Mid-cycle changes, free trials and part-month “stub” periods all need a rule written down before the first customer hits them. On a $100 plan, an 8-day stub in a 31-day month is $25.81.

• A failed payment means something different under each model, so plan the retry and recovery steps ahead of time.

• Use the change checklist whenever you touch pricing or billing, so nothing is discovered by a customer first.

Getting these layers straight feels like admin, but it’s the work that keeps your customers, your finance team and your support queue calm. Start with the one decision you’ve been putting off, write the rule down, and build from there. The examples in this guide use invented figures, so check them against your own plans.