Recurring Billing Software — Automated Invoicing & Dunning
Custom recurring billing software automates the full subscription cycle — it issues invoices on schedule, charges cards through Stripe, prorates plan changes to the day and chases failed payments with a dunning sequence. You get your own billing engine that tracks MRR in real time, with no monthly platform fee and no percentage cut on every transaction.
What the solution includes
We build a custom recurring payments system that runs on your backend and your subscriber base. You don't pay 0.5%–0.9% on revenue like off-the-shelf billing platforms — you pay for development once.
- ✓Plans, tiers and add-ons — monthly and annual pricing, free trials, multi-tier plans, metered billing (per-seat, per-usage) and add-ons attached to an existing subscription.
- ✓Proration — on upgrade, downgrade or cycle switch the system computes the exact difference down to the day and adds or credits it on the next invoice automatically.
- ✓Stripe integration and tokenization — card data never touches your server; SCA/3D Secure, SEPA Direct Debit and auto-capture via the Stripe Billing API.
- ✓Dunning and retry logic — a configurable retry-and-email sequence on failed payments that recovers 38–55% of otherwise lost subscribers.
- ✓Scheduled automated invoices — PDF and e-invoice generation with correct numbering, VAT logic and automatic email delivery on the renewal date.
- ✓MRR and churn analytics — a dashboard with MRR, ARR, net revenue retention, voluntary and involuntary churn, LTV and cohort analysis in real time.
- ✓Customer self-service portal — subscribers change card, switch plan, download invoices and cancel on their own, without emailing support.
- ✓Webhooks and accounting sync — every billing event flows to your ERP/CRM and accounting software via API integrations, with no manual re-keying.
Who it is for
A startup with 700 paying subscribers that has outgrown manual Excel invoices. The system bills per-seat when a user is added mid-cycle, prorates to the day and emails the invoice automatically — no accountant tracking every upgrade.
Gym chains, paywalled media, box subscriptions and B2B retainers. A card expires — the dunning sequence retries on day 1, 3 and 7 and emails an update link before the subscriber churns.
A marketing or IT agency with 40 retainer contracts on different amounts and dates. The billing software keeps each client on its own schedule, issues a VAT-compliant invoice and pushes revenue to accounting with no month-end reconciliation.
How we build it
We are not a reseller of a billing platform. We build the logic on the Stripe API and your backend, so pricing rules, subscribers and revenue data stay with you and can change without migration.
1. Modeling the pricing plans
We map every plan, cycle, trial, discount and add-on along with proration and tax rules. We define how the system behaves on a mid-month upgrade, a pause, a monthly-to-annual switch and reactivation of a cancelled subscription — before writing a line of code.
2. Billing engine and schedule
We build the core: invoice generator, proration calculator and a nightly cron that finds subscriptions due for renewal and creates the invoices. Every amount is computed idempotently — a re-run never charges twice, even if the job crashes.
3. Stripe and payments
We wire Stripe Billing and PaymentIntents with SCA/3D Secure, SEPA and a tokenized card vault. Card data goes straight to Stripe — outside your PCI scope. A webhook layer confirms every successful or failed capture and updates subscription status in real time.
4. Dunning and revenue recovery
We configure smart retries on failed payments (on days with a higher authorization rate), escalating emails, a grace period and controlled suspension when retries are exhausted. This chain typically recovers 38–55% of the MRR otherwise lost to expired cards.
5. Analytics, portal and go-live
We ship the MRR/churn dashboard, customer self-service portal and webhooks to ERP and accounting. We migrate existing subscribers without breaking their cycle, run shadow-mode alongside the old process for a month and only then cut over fully.
Why Saitami
Prices are fixed in EUR — you pay for development once, not a percentage on every invoice forever. Running the whole subscription business? See subscription business software; for quotes before the subscription — a quotes and invoicing system built on custom business software.
Frequently Asked Questions
How much does custom recurring billing software cost?
From €4,200 for a billing engine with Stripe integration, plans, proration and basic dunning. A full solution with MRR/churn analytics, customer portal, SEPA and accounting sync starts from €7,500. The only recurring cost is hosting and the Stripe processing fee — no percentage to a billing platform, which on off-the-shelf services can exceed €1,000/month at higher volume.
Why not use a ready platform like Stripe Billing or Chargebee?
Stripe Billing and similar cover standard cases but charge a percentage on revenue and limit non-standard proration, hybrid pricing and country-specific VAT logic. A custom system uses Stripe only to capture the payment, while the rules and data stay with you — no vendor lock-in and no fee that grows as your MRR grows.
What happens on a failed card payment?
A dunning sequence starts: automatic retries on days with a higher authorization rate, escalating emails with a card-update link, a grace period with continued access and finally a controlled suspension. The whole chain is configurable by attempt count, intervals and copy and typically recovers 38–55% of otherwise lost subscribers.
Can you migrate our existing subscribers without disruption?
Yes. We import subscribers, plans and renewal dates, tokenize cards through Stripe Customer migration and run the new system in shadow-mode alongside the old process for about a month. We compare generated invoices line by line and cut over fully only once the amounts match 100%.
Does the system issue VAT-compliant invoices?
Yes. The billing engine generates invoices with correct sequential numbering, the right VAT rate, EU B2B reverse charge and automatically pushes revenue data to your accounting software via webhook, so accounting enters nothing by hand.
Ready to automate subscription billing?
Send us your pricing plans and active subscriber count. Within 3 business days we prepare a billing-engine architecture, a dunning strategy and a fixed EUR quote.
Request a billing system quote →Related services: custom software · integrations · subscription business software