Supabase vs Firebase 2026 | B2B App Comparison

Supabase and Firebase can both support a B2B application, but “SQL versus NoSQL” is an incomplete description of the choice. Firebase includes several database products, including a PostgreSQL option. Start with the data model and the specific services the application will use.

Product and pricing details checked on 15 September 2026. Recommendations below are design judgements, not benchmark results.

Compare Specific Databases

Supabase centres its platform on PostgreSQL. For a client portal, tables, relationships, and database policies can be useful when customers, users, invoices, and permissions need to be joined or reported on.

Cloud Firestore is Firebase’s document database. It organises records into collections and documents. Design queries, indexes, and access rules around the application’s reads and writes rather than assuming relational SQL behaviour.

Firebase SQL Connect, previously Data Connect, provides a relational option backed by Cloud SQL for PostgreSQL. It offers schema and operation definitions with generated client SDKs. A Firebase application does not have to begin with Firestore or operate two databases to use SQL. See the SQL Connect documentation.

The practical comparison is therefore Supabase versus the appropriate Firebase database and supporting services, not Supabase versus every Google database as one product.

Questions That Affect the Choice

Application need	What to investigate
Tenant relationships, reports, and joins	PostgreSQL schema and query design in Supabase or SQL Connect
Document synchronisation	Firestore queries, listeners, indexes, and client behaviour
Offline operation	Support in the exact SDK and data service you will deploy
Authentication	Required login methods, account linking, roles, and billing
File uploads	Storage permissions, upload limits, delivery, and transfer charges
Server processing	Runtime, duration, network access, and deployment workflow
Migration	Database export plus auth, storage, policies, functions, and application changes

A feature being available does not establish which platform implements your use case better. Build a small example of the hardest requirement, such as tenant-isolated reporting or editing records while offline.

Pricing: User Count Is Not a Workload

Supabase Pro starts at $25 per month. The pricing calculator includes $10 of monthly compute credit; one Micro project is shown at $10 of compute, offset by that credit. Extra projects, larger compute, usage beyond allowances, and add-ons can increase the bill. Check the Supabase pricing page for the configuration you intend to deploy.

Firestore charges for operations, storage, and network use, with details that depend on query shape. Listener billing is not simply “resend the entire collection on every change”: document additions and updates in a result set incur reads, and reconnect behaviour can create additional charges. Some queries also incur index-entry reads. See Firestore billing.

SQL Connect has its own service and Cloud SQL costs. Do not apply Firestore read/write prices to that product.

For a cost estimate, record:

Active users and the number of sessions each generates.
Queries and writes per session, including listeners and background jobs.
Database size, file storage, transfer, and retention.
Compute, environments, backups, and paid authentication features.
Engineering time for schema changes, support, and recovery.

A “10,000 users” price without those inputs cannot support a reliable comparison. Use USD list prices with a stated billing period, then apply exchange rates and tax separately.

Portability and Operations

Standard PostgreSQL data can be easier to move between PostgreSQL hosts, but a database export is only part of a Supabase migration. Authentication, storage, realtime subscriptions, functions, and application dependencies still need a migration plan.

A Firestore migration may require a different data model and query layer. SQL Connect uses PostgreSQL underneath, but its generated API and client integration are also dependencies. Evaluate what must change in the application as well as what data can be exported.

For either choice, test tenant isolation, backup restoration, and failed writes. Local development tools help catch errors; they do not replace testing the deployed configuration.

Decision Framework

Consider Supabase when PostgreSQL fits the domain and your team wants to manage schema, queries, and policies directly within that platform.

Consider Firestore when document access and its client synchronisation behaviour suit the product. Confirm the queries and reporting path before committing.

Consider SQL Connect when you want PostgreSQL within Firebase’s development approach. Compare its API workflow and total costs with Supabase on the same feature.

The team maintaining the application matters as much as the initial prototype. If the process is still changing or an existing product meets the need, revisit whether a custom app is necessary before choosing its backend.

Where Fernside Fits

We advise on backend choice as part of advisory. data model, tenancy, and cost at your actual user counts, not a feature checklist. If the app needs operational AI on top of that data, that sits with AI systems.

Need architecture advice for a B2B app? Book a discovery call and we will tell you if Supabase, Firebase, or neither is the honest answer.