Can you build a SaaS without spending anything?
You can — and more than that, this is the best moment in history to do it. Tools that used to cost hundreds of dollars a month (managed databases, authentication, scalable hosting, email delivery) now have free tiers generous enough to validate a real idea, with real users, before you spend a single cent.
The secret isn't "use everything for free forever." It's choosing a stack where the free tier covers the validation phase, and the upgrade only happens once the product is already generating revenue.
Never pay for infrastructure before you have your first user. Let the tooling grow alongside your SaaS — not ahead of it.
The free stack to get started
Vercel — Hosting
Free deployment for Next.js, React, Astro, and similar projects. Automatic deploys on every GitHub push, HTTPS included, a free domain (.vercel.app subdomain), and a global CDN with zero configuration.
Supabase — Database & Auth
Managed Postgres, ready-made authentication (email, Google, etc.), file storage, and an automatic API — all on the free tier, no credit card required.
GitHub — Code & CI/CD
Unlimited private repositories for free. Connects directly to Vercel: every push already becomes a new deploy, with no server of your own.
Resend — Email Delivery
Transactional emails (signup confirmation, password recovery, notifications) with a generous monthly free tier and simple API integration.
Stripe — Payments
No monthly fee — just a per-transaction charge. In other words: it only costs something once your SaaS is already making sales.
Shadcn/UI + Tailwind — Interface
Ready-made, open-source components with no license fees. Build a professional interface without paying for a template or design system.
Supabase, Vercel, and GitHub don't ask for a credit card on their free tiers. Stripe does, but it only charges you on actual sales. Be wary of any "free plan" that asks for a card upfront — it's usually a trial in disguise.
Step by step: from zero to your first deploy
Before opening your editor, write down in one sentence what pain point you're solving and for whom. A SaaS born from technology ("I want to use AI") dies; a SaaS born from a real pain point ("barbershop owners waste time confirming appointments over WhatsApp") survives.
Create the project with create-next-app, push it to a private GitHub repository. Next.js handles both frontend and backend (API routes) in the same project — no need for a separate server.
Import the repository into Vercel in a few clicks. From here on, every push to the main branch automatically generates a new deploy, with its own URL for testing.
Create a free project on Supabase, model your main tables (users, plans, product data), and connect it via environment variables on Vercel. In minutes you have Postgres + API + authentication ready to go.
Sign-up, login, and the core feature — that's it. No fancy admin panel, reports, or automations yet. The goal is to have something a real user can test as soon as possible.
Put it in the hands of 5 to 10 people from your target audience. Only after seeing real usage — and someone willing to pay — connect Stripe to start charging.
Most SaaS products that never launch get stuck at step 5, trying to make everything perfect before showing it to anyone. Ship early, ugly, and functional — refinements come later, driven by feedback from paying users.
Comparison: what each free tier actually offers
Free tiers have real limits (bandwidth, database rows, emails). For a SaaS in validation, with a few dozen or a few hundred users, they're rarely hit. Check each service's dashboard monthly so you're not caught off guard.
Common myths about building a SaaS for free
Vercel and Supabase run on enterprise-grade infrastructure (AWS, GCP) behind the scenes — you get more reliability by managing less, not the other way around.
Thousands of real SaaS products, including ones with millions of dollars in revenue, run on Supabase and Vercel. The plan is free; the infrastructure behind it is the same as the paid tiers.
During the validation phase, the most efficient distribution is direct conversation with your target audience (WhatsApp groups, niche communities, cold outreach) — zero cost, immediate feedback.
Checklist before launching the first version
- Domain — Your own domain ($10–$15/year) already conveys more credibility than a
.vercel.appsubdomain - Working authentication — Sign-up, login, and password recovery tested end to end
- One core flow, no broken shortcuts — Better to have one flawless feature than five half-finished ones
- Basic analytics — Vercel Analytics or Plausible (free/low cost) to know who's using what
- A direct feedback channel — WhatsApp, email, or a simple form for users to report issues
- A clear pricing page — Even with a single plan, make explicit what's free and what will be paid
When it's worth starting to pay
No stack stays free forever — and it shouldn't. The tipping point is always the same: when the product already generates enough revenue or usage to justify the investment. Signs it's time to upgrade:
- Your user base is approaching the free tier's limit (database, storage, or emails)
- You have your first paying customers — the SaaS is already paying for itself
- You need priority support or a stronger SLA
- Traffic volume demands more performance or bandwidth
Vercel for hosting, Supabase for database and authentication, GitHub for version control, Resend for email, and Stripe to charge only once you have sales. With this combination, you can have a real SaaS live without spending anything — and only pay once the product is already sustaining itself.