PostgreSQL is powerful. But like any powerful system, it only performs at its full potential when handled with intention. Over the past few years, we’ve seen startups burn months of runway because of slow queries, bloated schemas, missing indexes, and “we’ll fix it later” architecture decisions.

This guide distills the same advice we give to our SaaS clients across the US and Europe — pragmatic, founder-friendly, and battle-tested.

Let’s get straight into it.

TL;DR

If you’re building a SaaS product in 2026, don’t just use PostgreSQL—use it well. These best practices help founders avoid costly pitfalls, boost performance, reduce cloud spend, and keep your product scalable without drama.

1. Design Your Schema Like You’ll Have 1 Million Users (Even If You Don’t Yet)

You don’t need to over-engineer, but you should avoid decisions that will punish you later.

Here’s what “future-proof without overkill” looks like:

Use UUIDs, not auto-increment IDs

They make sharding, distributed systems, and multi-region deployments far easier.

Normalize first, denormalize only when needed

Every founder says they’ll never rewrite the database. Every founder eventually rewrites the database.
Good normalization delays that pain.

Use proper data types: avoid varchar everywhere

If something is an integer, store it as integer.
If it's JSON, use JSONB.
If it’s a timestamp, don’t store it as text.
These small decisions matter at scale.

2. Indexing Is Not Optional — It’s Engineering Discipline

Slow queries rarely come from PostgreSQL being “weak.”
They come from missing indexes.

Critical reminders:

Index foreign keys

99% of SaaS founders forget this.
Your joins will thank you later.

Use partial indexes only when the data distribution justifies it

Example: status = 'active' items in a large table.

Avoid indexing everything

Every index speeds reads but slows writes.
Balance is key.

Think of indexes like gym workouts — correct ones make you stronger; unnecessary ones just burn energy.

3. Use JSONB Wisely — It’s a Feature, Not a Parking Lot

JSONB is fantastic, but treating it like a junk drawer leads to chaos.

Smart usage looks like this:

• for flexible attributes that vary per user

• for storing integrations data

• for rarely filtered fields

Never use JSONB for core relational data. That’s asking for pain.

4. Embrace Connection Pooling Early (Not After Outages)

Most SaaS outages trace back to too many open connections.

Always deploy with:

• PgBouncer

• or your cloud provider’s native pooling (Neon, Supabase, RDS Proxy)

Think of pooling as air traffic control.
Without it? Planes circle endlessly and nothing lands.

5. Adopt Row-Level Security (RLS) From Day One

If you’re building multi-tenant SaaS, this is not optional.

RLS makes tenant separation a database guarantee, not a “hope our backend checks it correctly.”

With RLS in place:

• Your app becomes safer

• Audits become easier

• Bugs become less catastrophic

Founders underestimate how big this is until they need it.

6. Treat Migrations Like Production Deployments (Because They Are)

Schema changes break things faster than code changes.

Best practices:

• Review migrations like real PRs

• Never run destructive migrations during peak traffic

• Use CONCURRENT indexes for zero-downtime needs

• Rollout changes in two phases: “add → backfill → remove”

A calm engineering team is a migration-disciplined team.

7. Monitor Everything — Not Just CPU and Memory

Real PostgreSQL health comes from:

• slow query logs

• autovacuum activity

• bloat statistics

• cache hit ratio

• deadlocks

You don’t need a complex observability stack.
Even simple dashboards prevent huge issues.

If you wait to monitor until “things feel slow,” you’re already late.

8. Keep Long Transactions Out of Your System

This is one of the stealthiest performance killers.

Long-running transactions:

• block vacuum

• increase table bloat

• degrade performance over hours

• can cause write locks

Treat them as emergencies.
No transaction should live “longer than your meeting.”

9. Avoid Premature Sharding — Partition Only When Needed

Sharding is expensive in time, cost, and engineering health.

Choose this only when:

• data is genuinely massive

• single-node scaling is exhausted

• business demands multi-region writes

Otherwise, use simpler partitioning approaches.

10. Use Extensions Thoughtfully — Postgres Has Superpowers

A few to consider for SaaS:

• pg_stat_statements → mandatory for visibility

• uuid-ossp → reliable UUID generation

• pgcrypto → secure hashing and encryption

• citext → case-insensitive text fields

• pg_trgm → fast fuzzy search

Extensions let you build sharper tools without overhead.

Final Takeaway

PostgreSQL is more than a database — it’s a long-term strategic asset.

The startups that thrive in 2026 aren’t the ones with the most features.
They’re the ones with the strongest, cleanest, most scalable foundations.

Following these best practices lets your SaaS grow without re-architecting every six months (or paying AWS bills that look like ransom notes).

If you're serious about building an investor-ready SaaS platform with real performance discipline, PostgreSQL gives you a winning foundation — if you use it right.