diff --git a/docs/production/export-and-import.md b/docs/production/export-and-import.md
index d03b22773f..571e8a7bf2 100644
--- a/docs/production/export-and-import.md
+++ b/docs/production/export-and-import.md
@@ -169,7 +169,7 @@ data includes:
   PostgreSQL server to add:
 
   ```ini
-  s3_region = # region to write to S3
+  s3_region = # region to write to S3; defaults to EC2 host's region
   s3_backups_key = # aws public key
   s3_backups_secret_key =  # aws secret key
   s3_backups_bucket = # name of S3 backup
diff --git a/puppet/zulip/files/postgresql/env-wal-g b/puppet/zulip/files/postgresql/env-wal-g
index 91e8112b6b..10cd39d8a0 100755
--- a/puppet/zulip/files/postgresql/env-wal-g
+++ b/puppet/zulip/files/postgresql/env-wal-g
@@ -4,7 +4,14 @@ if [ -z "$ZULIP_SECRETS_CONF" ]; then
 fi
 
 export PGHOST=/var/run/postgresql/
-AWS_REGION=$(crudini --get "$ZULIP_SECRETS_CONF" secrets s3_region)
+AWS_REGION=$(crudini --get "$ZULIP_SECRETS_CONF" secrets s3_region 2>/dev/null)
+if [ "$AWS_REGION" = "" ]; then
+    # Fall back to the current region, if possible
+    AZ=$(ec2metadata --availability-zone || true)
+    if [ -n "$AZ" ] && [ "$AZ" != "unavailable" ]; then
+        AWS_REGION=$(echo "$AZ" | sed 's/.$//')
+    fi
+fi
 export AWS_REGION
 AWS_ACCESS_KEY_ID=$(crudini --get "$ZULIP_SECRETS_CONF" secrets s3_backups_key)
 export AWS_ACCESS_KEY_ID