diff --git a/esphome/components/mqtt/mqtt_client.cpp b/esphome/components/mqtt/mqtt_client.cpp
index 6a7d91a02ab3..1cdf704d8394 100644
--- a/esphome/components/mqtt/mqtt_client.cpp
+++ b/esphome/components/mqtt/mqtt_client.cpp
@@ -723,6 +723,11 @@ void MQTTClientComponent::set_discovery_info(std::string &&prefix, MQTTDiscovery
   this->discovery_info_.object_id_generator = object_id_generator;
   this->discovery_info_.retain = retain;
   this->discovery_info_.clean = clean;
+  this->discovery_prefix_configured_ = this->discovery_info_.prefix;
+}
+
+void MQTTClientComponent::set_discovery_enabled(bool enabled) {
+  this->discovery_info_.prefix = enabled ? this->discovery_prefix_configured_ : "";
 }
 
 void MQTTClientComponent::disable_last_will() {
@@ -739,6 +744,7 @@ void MQTTClientComponent::disable_discovery() {
       .unique_id_generator = MQTT_LEGACY_UNIQUE_ID_GENERATOR,
       .object_id_generator = MQTT_NONE_OBJECT_ID_GENERATOR,
   };
+  this->discovery_prefix_configured_ = "";
 }
 void MQTTClientComponent::on_shutdown() {
   if (!this->shutdown_message_.topic.empty()) {
diff --git a/esphome/components/mqtt/mqtt_client.h b/esphome/components/mqtt/mqtt_client.h
index fe8f42b0cdec..88d8acb5dc5a 100644
--- a/esphome/components/mqtt/mqtt_client.h
+++ b/esphome/components/mqtt/mqtt_client.h
@@ -132,6 +132,8 @@ class MQTTClientComponent : public Component {
   const MQTTDiscoveryInfo &get_discovery_info() const;
   /// Globally disable Home Assistant discovery.
   void disable_discovery();
+  /// Flip discovery at run time; off keeps the configured prefix so a later on can restore it.
+  void set_discovery_enabled(bool enabled);
   bool is_discovery_enabled() const;
   bool is_discovery_ip_enabled() const;
 
@@ -314,6 +316,8 @@ class MQTTClientComponent : public Component {
       .unique_id_generator = MQTT_LEGACY_UNIQUE_ID_GENERATOR,
       .object_id_generator = MQTT_NONE_OBJECT_ID_GENERATOR,
   };
+  /// What set_discovery_enabled(true) restores; empty once discovery is off at build time.
+  std::string discovery_prefix_configured_{"homeassistant"};
   std::string topic_prefix_{};
   bool topic_prefix_auto_{true};
   bool birth_message_auto_{true};