3 Multi-Tenancy Patterns for SaaS — and When to Use Each

The three models

• Silo tenancy: each tenant gets their own database — maximum isolation, highest cost
• Pool tenancy: all tenants share one database with a tenant_id column — lowest cost, most complex isolation
• Bridge tenancy: separate schemas per tenant within one database — reasonable middle ground

When to use silo

Choose silo for strict data residency requirements, regulated industries, or very large per-tenant data volumes.

When to use pool

Choose pool when building a startup that needs to move fast and customers don't have isolation requirements. Pool is the default for 80% of B2B SaaS products we build.

Migration between models

Build your data access layer behind an abstraction from day one so migration doesn't require rewriting every query.