Three Patterns for Multi-Tenancy in Laravel, and When Each Breaks

Multi-tenancy decisions get made once, early, and are painful to reverse — so it's worth being honest about which pattern fits the actual customer count and compliance needs, not the pattern that's most fun to build.

Shared database, tenant column

The simplest to build and operate: every table gets a `tenant_id`, global scopes enforce isolation automatically. It scales well operationally — one database to back up, one to migrate — but a single missed scope is a data leak between customers, and it's the pattern most likely to fail a strict data-residency requirement.

Separate databases per tenant

Strongest isolation, and the natural choice once a customer demands their data live in a specific region or be fully separable for compliance. The cost shows up in migrations — running one migration across five hundred tenant databases needs real tooling — and in connection management at scale.

• Under ~50 tenants, no compliance pressure → shared database, tenant column, well-tested global scopes.
• Enterprise customers demanding data isolation → separate databases, budget for migration tooling from day one.
• Schema-per-tenant on Postgres is a solid middle ground if your host supports it well.
• Whatever pattern you pick, write a test that tries to leak data across tenants and run it in CI forever.

Multi-tenancy isn't an architecture decision you revisit lightly. Pick based on your actual compliance needs, not your most interesting Friday afternoon.