Subscription Billing for a SaaS: Build Cost in Toronto (2026)

The verdict in three sentences

If your SaaS is under roughly CA$400k ARR, start on Stripe Billing and keep your cash for acquisition. Beyond that, or if your plans are complex (usage, tiers, annual contracts with proration), a custom billing engine at CA$18k-CA$45k pays back in 12-18 months. The real win isn't the platform fee — it's recovering involuntary churn: -30 % failed payments means several points of MRR saved every month.

What must a SaaS billing engine cover in 2026?

Recurring billing isn't "charge a card every month." It's a system that manages the full subscription lifecycle: trials, prorated upgrades, downgrades, pauses, failed-payment retries (dunning) and tax compliance. Every missing brick costs revenue.

The two bricks that move the money are dunning and proration. A declined card with no smart retry is a lost customer who wanted to stay.

Custom build or a billing SaaS platform?

In 2026 the most common path for an SME SaaS is the hybrid: Stripe collects and handles PCI/SCA compliance, but your app drives plans, proration, dunning and MRR reporting. You keep the customer data and avoid the lock-in of a platform that charges a percentage on your entire volume.

Mini case study

Julien, co-founder of an HR SaaS in Toronto, 4,200 subscribers, ARPU CA$52/mo, ~CA$218k MRR. Involuntary churn runs at 9 % of renewals: about CA$1,900 in MRR lost every month for lack of retries. He invests CA$19k in an in-house dunning layer (retries at D+1, D+3, D+7, self-service card update, automatic plan switching). Result: involuntary churn down to 6 %, ~CA$630 MRR recovered monthly, +CA$7,560 annualized ARR. Payback in ~30 months on dunning alone — plus he gains clean proration and reliable MRR reporting for fundraising.

FAQ

How much does a custom SaaS billing engine cost?

Expect CA$18k-CA$45k by complexity: simple plans and proration at the low end, usage-based and multi-currency at the top. A hybrid layer on Stripe starts around CA$10k.

Is Stripe Billing enough for a Canadian SaaS?

Yes to start: SCA, tax and basic dunning are handled. The limit hits when you want specific proration rules, complex usage metering, or to avoid a percentage on high volume.

What is involuntary churn and why prioritize it?

It's losing customers who wanted to stay but whose payment failed (expired card, limit). It's often 20-40 % of total churn and 30 % recoverable with good dunning — the best ROI in billing.

How do we handle sales tax on subscriptions?

Apply the rate by jurisdiction (GST/HST/PST in Canada, or OSS in the EU for EU customers). A good engine computes the rate automatically by location and B2B/B2C status.

Can we migrate from Stripe Billing to custom later?

Yes, provided your subscriptions and history stay exportable. A hybrid architecture makes that gradual switch far easier without re-subscribing customers.

Let's scope your project. Tell us your plans, MRR volume and friction points (dunning, proration, tax): we'll price a custom or hybrid billing layer, typically CA$10k-CA$45k. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.