Best SaaS Starter Kits & Boilerplates

Every SaaS starter kit claims auth, billing, and a dashboard. The gap between a free one and a $299 one is in the parts that do not show up in a demo video: multi-tenancy (can one account belong to multiple organizations?), role-based access control, webhook handling for failed payments, and email deliverability config that does not land in spam. Free and open-source kits get you 70% of the way — authentication, a landing page, Stripe or Razorpay checkout. The paid tier buys you the boring infrastructure work: retry logic on failed webhooks, seat-based billing math, admin impersonation for support tickets. If your SaaS is pre-revenue, start free. Pay once you have paying customers and the free kit's gaps start costing you support time.

A starter kit built for solo-founder B2C products — fast auth, one pricing page, a Stripe Checkout redirect — will fight you if you are building B2B software with teams, seats, and invite flows, and you will spend more time ripping out the wrong abstractions than you would have spent building from scratch. Before comparing kits, answer three questions: do you need organizations (multiple users per paying account) or just individual accounts? Do you need usage-based billing or flat subscriptions? Do you need a mobile app or browser extension alongside the web app, or is this web-only? A kit optimized for fast solo launches and a kit optimized for B2B multi-tenancy solve different problems — the fastest kit for the wrong shape costs you more than the slowest kit for the right one.

Check these before you buy, not after: does the billing integration support Razorpay or only Stripe, a real blocker if you are selling in India? Is there a working webhook handler for subscription downgrades and failed payments, or just the happy-path checkout flow? Does the admin dashboard let you manually adjust a customer's plan without touching the database? And, the one everyone skips, is there a test suite, or will your first refactor be undocumented trial and error? A kit with real test coverage and clear webhook handling saves more time over six months than one with a prettier landing page and none of the above.