diff --git a/src/network.c b/src/network.c
index ac4942ba..eb0f7972 100644
--- a/src/network.c
+++ b/src/network.c
@@ -1405,6 +1405,14 @@ void ofono_netreg_strength_notify(struct ofono_netreg *netreg, int strength)
 	if (netreg->signal_strength == strength)
 		return;
 
+	/*
+	 * Theoretically we can get signal strength even when not registered
+	 * to any network.  However, what do we do with it in that case?
+	 */
+	if (netreg->status != NETWORK_REGISTRATION_STATUS_REGISTERED &&
+			netreg->status != NETWORK_REGISTRATION_STATUS_ROAMING)
+		return;
+
 	netreg->signal_strength = strength;
 
 	if (strength != -1) {