Replicating into Neon: enable logical replication on the source

TL;DR: # Subscribing Neon to an external publisher ## The trap Direction confusion: "enable logical replication" must happen where the data comes from. Replicating into Neon means the source (RDS, self-hosted Postgres, etc.) needs wal_level = logical

Fix

1. Subscribing Neon to an external publisher ## The trap Direction confusion: "enable logical replication" must happen where the data comes from.

   Expected: this specific failure stops.

2. and a restart, not your Neon project. ## The rule 1. Expected: this specific failure stops.

3. On the source database: set. Expected: this specific failure stops.

4. , restart, create the publication and replication slot. Expected: this specific failure stops.

5. must allow it. Expected: this specific failure stops.

Details

wal_level = logical wal_level = logical 2. In Neon: create the subscription pointing at the source with the direct connection details. 3. The replication connection originates from Neon toward the source; the source's firewall and pg_hba 4.

When to use

You hit exactly this: Replicating into Neon: enable logical replication on the source in Replicating into Neon.

When not to use

A different error, or the same symptom in a different tool. This page only covers the failure above.

Compatibility

Replicating into Neon.

Root cause

Replicating into Neon means the source (RDS, self-hosted Postgres, etc.) needs

Neon's logical replication guide (verified live 2026-09-26): when replicating data to Neon, enable logical replication on the source database instead; covers the publication/slot/subscription mechanics.