diff --git a/go.mod b/go.mod
index f31c04b8..2fb92ae3 100644
--- a/go.mod
+++ b/go.mod
@@ -13,7 +13,7 @@ require (
 	github.com/prometheus/common v0.70.1
 	github.com/spf13/pflag v1.0.10
 	github.com/stretchr/testify v1.12.1
-	github.com/unpoller/unifi/v6 v6.0.2
+	github.com/unpoller/unifi/v6 v6.0.3
 	go.opentelemetry.io/otel v1.46.0
 	go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc v1.46.0
 	go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp v1.46.0
diff --git a/go.sum b/go.sum
index 17e75164..8291259e 100644
--- a/go.sum
+++ b/go.sum
@@ -121,8 +121,8 @@ github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO
 github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
 github.com/stretchr/testify v1.12.1 h1:EuwCh5fleGS7H32xRwO3wRGT7DxrDhLAT6FF8MpWDWE=
 github.com/stretchr/testify v1.12.1/go.mod h1:MDEgiDPPsNp5cuIrHPPCyornHKgEVbtFUmoNlxoYthg=
-github.com/unpoller/unifi/v6 v6.0.2 h1:Mzcn0zSTnFxMZuFIoVqhSkECT1sX9S7RJ8e/ZxikOcw=
-github.com/unpoller/unifi/v6 v6.0.2/go.mod h1:d7dz1cBxVbbFZobNRcdUHHYtTdicVyZ05J5OmgoINa8=
+github.com/unpoller/unifi/v6 v6.0.3 h1:NoxbSA5HLMErs/1yVkmuwm+lcyy9SxSfOLDW58PKqrQ=
+github.com/unpoller/unifi/v6 v6.0.3/go.mod h1:d7dz1cBxVbbFZobNRcdUHHYtTdicVyZ05J5OmgoINa8=
 github.com/yuin/goldmark v1.3.5/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
 github.com/zeebo/assert v1.3.0 h1:g7C04CbJuIDKNPFHmsk4hwZDO5O+kntRxzaUoNXj+IQ=
 github.com/zeebo/assert v1.3.0/go.mod h1:Pq9JiuJQpG8JLJdtkwrJESF0Foym2/D9XMU5ciN/wJ0=
diff --git a/pkg/promunifi/wan.go b/pkg/promunifi/wan.go
index e40a12b2..4ffd15db 100644
--- a/pkg/promunifi/wan.go
+++ b/pkg/promunifi/wan.go
@@ -87,8 +87,8 @@ func (u *promUnifi) exportWAN(r report, w *unifi.WANEnrichedConfiguration) {
 		cfg.WANNetworkgroup,
 		cfg.WANType,
 		cfg.WANLoadBalanceType,
-		"", // site_name - will be set by caller if available
-		"", // source - will be set by caller if available
+		w.SiteName,
+		w.SourceName,
 	}
 
 	// Convert boolean FlexBool values to float64
@@ -130,8 +130,8 @@ func (u *promUnifi) exportWAN(r report, w *unifi.WANEnrichedConfiguration) {
 		cfg.WANNetworkgroup,
 		details.ServiceProvider.Name,
 		details.ServiceProvider.City,
-		"", // site_name
-		"", // source
+		w.SiteName,
+		w.SourceName,
 	}
 
 	metrics = append(metrics, &metric{u.WAN.ServiceProviderASN, gauge, details.ServiceProvider.ASN.Val, providerLabels})
diff --git a/pkg/promunifi/wan_test.go b/pkg/promunifi/wan_test.go
new file mode 100644
index 00000000..acf67747
--- /dev/null
+++ b/pkg/promunifi/wan_test.go
@@ -0,0 +1,69 @@
+//nolint:testpackage // white-box: exercises the unexported descriptors and export path.
+package promunifi
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"github.com/unpoller/unifi/v6"
+)
+
+func testWANConfig() *unifi.WANEnrichedConfiguration {
+	return &unifi.WANEnrichedConfiguration{
+		SiteName:   "Default (default)",
+		SourceName: "https://udr.example",
+		Configuration: unifi.WANConfiguration{
+			ID:                 "a1",
+			Name:               "Internet 1",
+			WANNetworkgroup:    "WAN",
+			WANType:            "dhcp",
+			WANLoadBalanceType: "weighted",
+		},
+		Details: unifi.WANDetails{
+			ServiceProvider: unifi.WANServiceProvider{
+				Name: "SpaceX Starlink",
+				City: "Brussels",
+			},
+		},
+	}
+}
+
+// TestExportWANIsAttributed is the point of this change. Every unpoller_wan_*
+// series used to ship with empty site_name and source, which makes the metrics
+// of two controllers polled by the same instance indistinguishable. The only
+// way to attribute them downstream was to hardcode a mapping in the scrape
+// config and hope no second controller ever gained a gateway.
+func TestExportWANIsAttributed(t *testing.T) {
+	t.Parallel()
+
+	r := &fakeReport{}
+	u := &promUnifi{WAN: descWAN("unifi_")}
+	u.exportWAN(r, testWANConfig())
+
+	require.NotEmpty(t, r.sent, "a WAN configuration must produce metrics")
+
+	a := assert.New(t)
+
+	for _, m := range r.sent {
+		require.GreaterOrEqual(t, len(m.Labels), 7, "every WAN metric carries the base label set")
+		// site_name and source are the last two of the base label set; the
+		// provider descriptors substitute isp_name/isp_city earlier but keep
+		// the same trailing pair.
+		a.Equal("Default (default)", m.Labels[len(m.Labels)-2], "site_name must be populated")
+		a.Equal("https://udr.example", m.Labels[len(m.Labels)-1], "source must be populated")
+		a.NotContains(m.Labels[:len(m.Labels)-2], "", "no other label should be blank in this fixture")
+	}
+}
+
+// TestExportWANNilIsSafe pins the existing guard: the collector iterates over
+// whatever the input plugin produced, and a nil entry must not panic a poll.
+func TestExportWANNilIsSafe(t *testing.T) {
+	t.Parallel()
+
+	r := &fakeReport{}
+	u := &promUnifi{WAN: descWAN("unifi_")}
+	u.exportWAN(r, nil)
+
+	assert.Empty(t, r.sent, "a nil WAN configuration produces nothing and does not panic")
+}