diff --git a/net/interfaces/interfaces.go b/net/interfaces/interfaces.go
index f2988af34..d04b75177 100644
--- a/net/interfaces/interfaces.go
+++ b/net/interfaces/interfaces.go
@@ -500,7 +500,8 @@ func isPrivateIP(ip netaddr.IP) bool {
 }
 
 func isGlobalV6(ip netaddr.IP) bool {
-	return v6Global1.Contains(ip)
+	return v6Global1.Contains(ip) ||
+		(tsaddr.IsULA(ip) && !tsaddr.TailscaleULARange().Contains(ip))
 }
 
 func mustCIDR(s string) netaddr.IPPrefix {
diff --git a/net/interfaces/interfaces_test.go b/net/interfaces/interfaces_test.go
index ab0ee3734..fb7b213c2 100644
--- a/net/interfaces/interfaces_test.go
+++ b/net/interfaces/interfaces_test.go
@@ -7,6 +7,8 @@ package interfaces
 import (
 	"encoding/json"
 	"testing"
+
+	"inet.af/netaddr"
 )
 
 func TestGetState(t *testing.T) {
@@ -43,3 +45,24 @@ func TestLikelyHomeRouterIP(t *testing.T) {
 	}
 	t.Logf("myIP = %v; gw = %v", my, gw)
 }
+
+func TestIsGlobalV6(t *testing.T) {
+	tests := []struct {
+		name string
+		ip   string
+		want bool
+	}{
+		{"first ULA", "fc00::1", true},
+		{"Tailscale", "fd7a:115c:a1e0::1", false},
+		{"Cloud Run", "fddf:3978:feb1:d745::1", true},
+		{"zeros", "0000:0000:0000:0000:0000:0000:0000:0000", false},
+		{"Link Local", "fe80::1", false},
+		{"Global", "2602::1", true},
+	}
+
+	for _, test := range tests {
+		if got := isGlobalV6(netaddr.MustParseIP(test.ip)); got != test.want {
+			t.Errorf("isGlobalV6(%s) = %v, want %v", test.name, got, test.want)
+		}
+	}
+}