What does subscription and recurring billing cost to build?

Subscription billing looks simple from the outside: charge the card every month, send a receipt. The reality is that the moment real users start paying real money, every edge case you skipped in planning shows up as a support ticket or a lost customer.

A properly built recurring billing system costs $12,000–$18,000 with an experienced team. That number accounts for the payment logic, the billing calendar, failed-payment recovery, tax handling, and the compliance requirements that come with storing payment credentials. Western agencies charge $40,000–$60,000 for identical scope. The difference is workflow efficiency and overhead, not the quality of the output.

Here is what actually drives that cost, and what happens after the system goes live.

Every subscription cycle runs through four steps: calculate what the customer owes, attempt to charge their saved payment method, record the outcome, and decide what to do if the charge fails. That sequence sounds mechanical until you factor in prorated upgrades mid-cycle, annual plans with monthly breakdowns, free trial expirations, and customers who change plans the day before renewal.

The billing calendar is the most underestimated piece of this. A monthly subscriber who signs up on January 31st creates an immediate problem: February has no 31st. Neither do April, June, September, or November. Every billing engine needs rules for how to handle that, and those rules need to be consistent across every subscription in the database, not handled case by case when a customer complains.

Proration adds another layer. When a customer upgrades from a $29/month plan to a $79/month plan halfway through the billing cycle, they should be charged $25 for the remaining half of their old plan and $39.50 for the remaining half of their new one, a net charge of $64.50, not $79. Getting this right matters because customers notice when they are overcharged, and chargeback disputes cost $15–$25 per incident on top of the disputed amount (Chargebacks911, 2022).

A billing engine that handles all of this cleanly takes three to four weeks to build. An engineering team that has built one before will recognize the edge cases during scoping. A team that has not will find them in production.

For most SaaS products launching in 2022, the answer is Stripe, and the reasoning is straightforward.

Stripe Billing handles the billing calendar, proration logic, invoice generation, and payment retry scheduling out of the box. Braintree offers similar functionality with slightly different pricing, and works well for businesses that already process payments through PayPal. A custom billing engine makes sense only when your business model is genuinely unusual: usage-based pricing that changes by the second, or a marketplace that splits subscription revenue across multiple vendors before settlement.

The cost difference matters here. Building on Stripe Billing takes a skilled team roughly two to three weeks and costs $8,000–$12,000 in engineering time. Building a custom engine from scratch, with its own billing calendar, retry logic, and invoice renderer, takes eight to twelve weeks and costs $35,000–$50,000. Stripe charges 0.5–0.8% of subscription revenue as its platform fee, which on $100,000 of monthly recurring revenue adds up to $500–$800 per month. A custom engine eliminates that fee but requires your own team to maintain it.

Western agencies quoting $15,000–$20,000 just for Stripe integration are not doing more work. They are billing at $150–$200 per hour for a two-to-three-week project that a team working at AI-native rates completes for $8,000–$12,000. The underlying code is the same.

Three costs catch founders off guard after launch.

Tax remittance is the one nobody plans for. In the United States, SaaS products sold to customers in states that tax software subscriptions, including New York, Texas, and Pennsylvania, require the seller to collect and remit sales tax. Internationally, EU customers trigger VAT obligations once you cross the registration threshold in any member state. A tax calculation service like TaxJar or Avalara costs $99–$299 per month and handles this automatically. Building the same logic by hand takes four to six weeks and still requires a tax attorney to verify it. The service is the obvious choice, but it needs to be wired into your billing system before your first taxable sale.

Invoice and receipt infrastructure is the second. Customers expect professional PDF invoices emailed automatically at renewal. Enterprise customers often require invoices with their company name, billing address, VAT number, and purchase order reference. Building a flexible invoice renderer that handles all of those fields, exports a clean PDF, and sends it reliably takes one to two weeks. Founders who skip this get support tickets every billing cycle.

Plan migration logic is the third. When you change your pricing, which every SaaS product eventually does, you need a way to grandfather existing subscribers, migrate others to the new structure, and communicate the changes clearly. The billing system needs to support multiple concurrent price structures. Teams that build a single hardcoded price list find themselves doing a manual database migration every time pricing changes.

These three line items add $4,000–$6,000 to the initial build and another $100–$400 per month in ongoing service costs. They are not optional if you are running a real business.

The industry average for involuntary churn, subscribers who wanted to stay but lost access because their payment failed, sits at 9% of monthly recurring revenue (Profitwell, 2022). A $50,000 MRR business is leaking $4,500 every month from expired cards and insufficient funds. Recovering that revenue requires a dunning system.

Dunning is the process of automatically retrying failed payments on a schedule, emailing the customer to update their card, and downgrading or canceling their account if the payment cannot be collected after a defined window. Stripe's built-in Smart Retries use payment network data to pick the best time to retry; recovery rates with Smart Retries run about 38% higher than a fixed retry schedule (Stripe, 2021).

Building dunning on top of Stripe adds one to two weeks of engineering work. The system needs to handle at least four states: payment failed, first retry in 72 hours, customer notified by email, final retry before access is revoked. Each state triggers a different email, a different account status, and a different entry in the payment history.

For a team charging $8,000–$12,000 for the base billing integration, dunning adds $3,000–$5,000. Western agencies bill this as a separate project at $10,000–$18,000. The logic is not more complex when quoted at the higher rate; the rate itself is the explanation.

A subscription product with no dunning system is not just leaving revenue on the table. It is actively penalizing customers who want to stay by canceling them for a card decline they may not even know happened.

Storing payment data means operating under PCI DSS, the Payment Card Industry Data Security Standard. The specific requirements depend on how your system handles card numbers.

If your checkout is built on Stripe's hosted payment pages or Stripe Elements, card numbers never touch your servers. Your customers type their card into a form that sends data directly to Stripe. You see a token, not the card. This approach puts you in PCI SAQ A, the lowest compliance tier; it requires completing a self-assessment questionnaire rather than an on-site audit. Building on Stripe's hosted tools with this architecture takes one to two weeks and keeps compliance manageable from day one.

If your system passes raw card numbers through your own servers at any point, even briefly, you enter a higher compliance tier that requires quarterly vulnerability scans, network segmentation, and in some cases a third-party audit. The engineering cost to maintain that posture runs $8,000–$15,000 per year in addition to the initial build.

For most SaaS products, the right answer is to build on Stripe's hosted tools and stay in SAQ A. The engineering is simpler, the compliance cost is minimal, and the customer experience is identical to a custom-built checkout. Moving off that path requires a clear business reason, and a legal and compliance budget to match.

Storing payment data also triggers GDPR obligations for European customers and CCPA obligations for California residents. Both require a privacy policy that covers payment data retention, a defined deletion process when a customer cancels, and documented policies for what happens in the event of a data breach. These are not engineering tasks, but they affect how the billing system is built: specifically, how long payment records are retained and what a customer-initiated deletion removes from the database.

Building subscription and recurring billing correctly the first time costs $12,000–$18,000 with a team that has done it before. That includes the billing engine, dunning, tax integration, invoice generation, and a compliance-safe checkout. The teams that try to do it for $5,000 end up rebuilding pieces of it six months later when the edge cases emerge, usually at $200 per hour, mid-sprint, with users already affected.

If you are scoping a subscription product and want a detailed breakdown of what your specific billing model will require, Book a free discovery call.