SSL connection closed: Neon requires SSL, set sslmode

SSL failures: Neon requires encrypted connections

Symptom

SSL connection has been closed unexpectedly, ssl send: closed, or handshakes that die immediately.

Cause

Neon requires SSL for Postgres connections. Clients with SSL disabled or misconfigured (some ORMs default it off, some Java tools need it set explicitly) get their connection killed during negotiation.

Confirm

1. The connection string or client config lacks sslmode=require (or the driver's TLS equivalent).
2. Same string with ?sslmode=require appended connects fine.

Fix

• Add sslmode=require to the connection string: postgresql://[host]/[db]?sslmode=require (with your role and password in the userinfo section as usual).
• In framework config use the documented TLS option (Django: OPTIONS: {"sslmode": "require"}; similar per driver).
• Do not disable certificate verification to "fix" this; require is the point.

Verify

Clean connects from every client type you run (app, migrations, scripts, BI).

Neon's Django guide (verified live 2026-09-26) sets OPTIONS sslmode require; the connection error docs list Postgrex/SSL closed-connection errors among resolved issues; Neon's connect strings include sslmode=require by default.