diff --git a/netbird-server/DOCS.md b/netbird-server/DOCS.md
index e6caa470b..556fecf6f 100644
--- a/netbird-server/DOCS.md
+++ b/netbird-server/DOCS.md
@@ -16,7 +16,7 @@ NetBird relies on gRPC. The built-in Caddy configuration is pre-wired to proxy b
 This add-on generates the standard quickstart configuration files in `/config/netbird` and reuses them on subsequent starts.
 
 ### Required options
-- `domain`: Public domain that resolves to your Home Assistant host (e.g., `netbird.example.com`).
+- `domain`: Public domain that resolves to your Home Assistant host (e.g., `netbird.example.com`). If left at the default placeholder, the add-on will try to use the host from Home Assistant's `external_url` or `internal_url` instead.
 
 ### Dashboard environment overrides
 Edit `/config/netbird/dashboard/env` to configure the dashboard UI:
diff --git a/netbird-server/rootfs/etc/cont-init.d/00-config.sh b/netbird-server/rootfs/etc/cont-init.d/00-config.sh
index a31c7008f..c233205ae 100755
--- a/netbird-server/rootfs/etc/cont-init.d/00-config.sh
+++ b/netbird-server/rootfs/etc/cont-init.d/00-config.sh
@@ -33,8 +33,20 @@ SIGNAL_GRPC_PORT=10000
 RELAY_PORT=8084
 
 if [[ -z "$DOMAIN" || "$DOMAIN" == "netbird.example.com" ]]; then
-  bashio::log.error "Set a valid domain in the add-on configuration (domain cannot be empty or netbird.example.com)."
-  bashio::exit.nok
+  result=$(bashio::api.supervisor GET /core/api/config true || true)
+  external_host="$(bashio::jq "$result" '.external_url' | cut -d'/' -f3 | cut -d':' -f1)"
+  internal_host="$(bashio::jq "$result" '.internal_url' | cut -d'/' -f3 | cut -d':' -f1)"
+
+  if [[ -n "$external_host" && "$external_host" != "null" ]]; then
+    DOMAIN="$external_host"
+    bashio::log.warning "Domain not set; using Home Assistant external_url host: ${DOMAIN}"
+  elif [[ -n "$internal_host" && "$internal_host" != "null" ]]; then
+    DOMAIN="$internal_host"
+    bashio::log.warning "Domain not set; using Home Assistant internal_url host: ${DOMAIN}"
+  else
+    bashio::log.error "Set a valid domain in the add-on configuration (domain cannot be empty or netbird.example.com)."
+    bashio::exit.nok
+  fi
 fi
 
 NETBIRD_PORT=443