diff --git a/esphome/components/number/automation.cpp b/esphome/components/number/automation.cpp
index bfc59d0465..78ffc255fe 100644
--- a/esphome/components/number/automation.cpp
+++ b/esphome/components/number/automation.cpp
@@ -1,8 +1,7 @@
 #include "automation.h"
 #include "esphome/core/log.h"
 
-namespace esphome {
-namespace number {
+namespace esphome::number {
 
 static const char *const TAG = "number.automation";
 
@@ -52,5 +51,4 @@ void ValueRangeTrigger::on_state_(float state) {
   this->rtc_.save(&in_range);
 }
 
-}  // namespace number
-}  // namespace esphome
+}  // namespace esphome::number
diff --git a/esphome/components/number/automation.h b/esphome/components/number/automation.h
index 79eba883c4..a7cd04f083 100644
--- a/esphome/components/number/automation.h
+++ b/esphome/components/number/automation.h
@@ -4,8 +4,7 @@
 #include "esphome/core/automation.h"
 #include "esphome/core/component.h"
 
-namespace esphome {
-namespace number {
+namespace esphome::number {
 
 class NumberStateTrigger : public Trigger<float> {
  public:
@@ -91,5 +90,4 @@ template<typename... Ts> class NumberInRangeCondition : public Condition<Ts...>
   float max_{NAN};
 };
 
-}  // namespace number
-}  // namespace esphome
+}  // namespace esphome::number
diff --git a/esphome/components/number/number.cpp b/esphome/components/number/number.cpp
index f12e0e9e1e..992100ead0 100644
--- a/esphome/components/number/number.cpp
+++ b/esphome/components/number/number.cpp
@@ -3,8 +3,7 @@
 #include "esphome/core/controller_registry.h"
 #include "esphome/core/log.h"
 
-namespace esphome {
-namespace number {
+namespace esphome::number {
 
 static const char *const TAG = "number";
 
@@ -43,5 +42,4 @@ void Number::add_on_state_callback(std::function<void(float)> &&callback) {
   this->state_callback_.add(std::move(callback));
 }
 
-}  // namespace number
-}  // namespace esphome
+}  // namespace esphome::number
diff --git a/esphome/components/number/number.h b/esphome/components/number/number.h
index da91d70d53..472e06ad61 100644
--- a/esphome/components/number/number.h
+++ b/esphome/components/number/number.h
@@ -6,8 +6,7 @@
 #include "number_call.h"
 #include "number_traits.h"
 
-namespace esphome {
-namespace number {
+namespace esphome::number {
 
 class Number;
 void log_number(const char *tag, const char *prefix, const char *type, Number *obj);
@@ -53,5 +52,4 @@ class Number : public EntityBase {
   CallbackManager<void(float)> state_callback_;
 };
 
-}  // namespace number
-}  // namespace esphome
+}  // namespace esphome::number
diff --git a/esphome/components/number/number_call.cpp b/esphome/components/number/number_call.cpp
index 669dd65184..27a857c112 100644
--- a/esphome/components/number/number_call.cpp
+++ b/esphome/components/number/number_call.cpp
@@ -2,8 +2,7 @@
 #include "number.h"
 #include "esphome/core/log.h"
 
-namespace esphome {
-namespace number {
+namespace esphome::number {
 
 static const char *const TAG = "number";
 
@@ -125,5 +124,4 @@ void NumberCall::perform() {
   this->parent_->control(target_value);
 }
 
-}  // namespace number
-}  // namespace esphome
+}  // namespace esphome::number
diff --git a/esphome/components/number/number_call.h b/esphome/components/number/number_call.h
index 807207f0ec..0f6889dcb6 100644
--- a/esphome/components/number/number_call.h
+++ b/esphome/components/number/number_call.h
@@ -4,8 +4,7 @@
 #include "esphome/core/log.h"
 #include "number_traits.h"
 
-namespace esphome {
-namespace number {
+namespace esphome::number {
 
 class Number;
 
@@ -44,5 +43,4 @@ class NumberCall {
   bool cycle_;
 };
 
-}  // namespace number
-}  // namespace esphome
+}  // namespace esphome::number
diff --git a/esphome/components/number/number_traits.cpp b/esphome/components/number/number_traits.cpp
index 89035661f5..1e4239ceca 100644
--- a/esphome/components/number/number_traits.cpp
+++ b/esphome/components/number/number_traits.cpp
@@ -1,10 +1,8 @@
 #include "esphome/core/log.h"
 #include "number_traits.h"
 
-namespace esphome {
-namespace number {
+namespace esphome::number {
 
 static const char *const TAG = "number";
 
-}  // namespace number
-}  // namespace esphome
+}  // namespace esphome::number
diff --git a/esphome/components/number/number_traits.h b/esphome/components/number/number_traits.h
index fa68c2390a..5ccbb9ba48 100644
--- a/esphome/components/number/number_traits.h
+++ b/esphome/components/number/number_traits.h
@@ -3,8 +3,7 @@
 #include "esphome/core/entity_base.h"
 #include "esphome/core/helpers.h"
 
-namespace esphome {
-namespace number {
+namespace esphome::number {
 
 enum NumberMode : uint8_t {
   NUMBER_MODE_AUTO = 0,
@@ -35,5 +34,4 @@ class NumberTraits : public EntityBase_DeviceClass, public EntityBase_UnitOfMeas
   NumberMode mode_{NUMBER_MODE_AUTO};
 };
 
-}  // namespace number
-}  // namespace esphome
+}  // namespace esphome::number