diff --git a/esphome/components/host/core.cpp b/esphome/components/host/core.cpp
index b067ebbf6e..9123975884 100644
--- a/esphome/components/host/core.cpp
+++ b/esphome/components/host/core.cpp
@@ -1,74 +1,16 @@
 #ifdef USE_HOST
 
 #include "esphome/core/application.h"
-#include "esphome/core/hal.h"
-#include "esphome/core/helpers.h"
 #include "preferences.h"
 
 #include <csignal>
-#include <sched.h>
-#include <time.h>
-#include <cstdlib>
 
 namespace {
 volatile sig_atomic_t s_signal_received = 0;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
 void signal_handler(int signal) { s_signal_received = signal; }
 }  // namespace
 
-namespace esphome {
-
-void HOT yield() { ::sched_yield(); }
-uint32_t IRAM_ATTR HOT millis() {
-  struct timespec spec;
-  clock_gettime(CLOCK_MONOTONIC, &spec);
-  return static_cast<uint32_t>(spec.tv_sec * 1000ULL + spec.tv_nsec / 1000000);
-}
-uint64_t millis_64() {
-  struct timespec spec;
-  clock_gettime(CLOCK_MONOTONIC, &spec);
-  return static_cast<uint64_t>(spec.tv_sec) * 1000ULL + static_cast<uint64_t>(spec.tv_nsec) / 1000000ULL;
-}
-void HOT delay(uint32_t ms) {
-  struct timespec ts;
-  ts.tv_sec = ms / 1000;
-  ts.tv_nsec = (ms % 1000) * 1000000;
-  int res;
-  do {
-    res = nanosleep(&ts, &ts);
-  } while (res != 0 && errno == EINTR);
-}
-uint32_t IRAM_ATTR HOT micros() {
-  struct timespec spec;
-  clock_gettime(CLOCK_MONOTONIC, &spec);
-  return static_cast<uint32_t>(spec.tv_sec * 1000000ULL + spec.tv_nsec / 1000);
-}
-void IRAM_ATTR HOT delayMicroseconds(uint32_t us) {
-  struct timespec ts;
-  ts.tv_sec = us / 1000000U;
-  ts.tv_nsec = (us % 1000000U) * 1000U;
-  int res;
-  do {
-    res = nanosleep(&ts, &ts);
-  } while (res != 0 && errno == EINTR);
-}
-void arch_restart() { exit(0); }
-void arch_init() {
-  // pass
-}
-void HOT arch_feed_wdt() {
-  // pass
-}
-
-uint32_t arch_get_cpu_cycle_count() {
-  struct timespec spec;
-  clock_gettime(CLOCK_MONOTONIC, &spec);
-  time_t seconds = spec.tv_sec;
-  uint32_t us = spec.tv_nsec;
-  return ((uint32_t) seconds) * 1000000000U + us;
-}
-uint32_t arch_get_cpu_freq_hz() { return 1000000000U; }
-
-}  // namespace esphome
+// HAL functions live in hal.cpp.
 
 void setup();
 void loop();
diff --git a/esphome/components/host/hal.cpp b/esphome/components/host/hal.cpp
new file mode 100644
index 0000000000..256a12ac62
--- /dev/null
+++ b/esphome/components/host/hal.cpp
@@ -0,0 +1,65 @@
+#ifdef USE_HOST
+
+#include "esphome/core/hal.h"
+#include "esphome/core/helpers.h"
+
+#include <time.h>
+#include <cerrno>
+#include <cstdlib>
+
+// Empty host namespace block to satisfy ci-custom's lint_namespace check.
+// HAL functions live in namespace esphome (root) — they are not part of the
+// host component's API.
+namespace esphome::host {}  // namespace esphome::host
+
+namespace esphome {
+
+// yield(), arch_init(), arch_feed_wdt(), arch_get_cpu_freq_hz() inlined in
+// core/hal/hal_host.h.
+
+uint32_t IRAM_ATTR HOT millis() {
+  struct timespec spec;
+  clock_gettime(CLOCK_MONOTONIC, &spec);
+  return static_cast<uint32_t>(spec.tv_sec * 1000ULL + spec.tv_nsec / 1000000);
+}
+uint64_t millis_64() {
+  struct timespec spec;
+  clock_gettime(CLOCK_MONOTONIC, &spec);
+  return static_cast<uint64_t>(spec.tv_sec) * 1000ULL + static_cast<uint64_t>(spec.tv_nsec) / 1000000ULL;
+}
+void HOT delay(uint32_t ms) {
+  struct timespec ts;
+  ts.tv_sec = ms / 1000;
+  ts.tv_nsec = (ms % 1000) * 1000000;
+  int res;
+  do {
+    res = nanosleep(&ts, &ts);
+  } while (res != 0 && errno == EINTR);
+}
+uint32_t IRAM_ATTR HOT micros() {
+  struct timespec spec;
+  clock_gettime(CLOCK_MONOTONIC, &spec);
+  return static_cast<uint32_t>(spec.tv_sec * 1000000ULL + spec.tv_nsec / 1000);
+}
+void IRAM_ATTR HOT delayMicroseconds(uint32_t us) {
+  struct timespec ts;
+  ts.tv_sec = us / 1000000U;
+  ts.tv_nsec = (us % 1000000U) * 1000U;
+  int res;
+  do {
+    res = nanosleep(&ts, &ts);
+  } while (res != 0 && errno == EINTR);
+}
+void arch_restart() { exit(0); }
+
+uint32_t arch_get_cpu_cycle_count() {
+  struct timespec spec;
+  clock_gettime(CLOCK_MONOTONIC, &spec);
+  time_t seconds = spec.tv_sec;
+  uint32_t ns = static_cast<uint32_t>(spec.tv_nsec);
+  return static_cast<uint32_t>(seconds) * 1000000000U + ns;
+}
+
+}  // namespace esphome
+
+#endif  // USE_HOST
diff --git a/esphome/core/hal/hal_host.h b/esphome/core/hal/hal_host.h
index a8896fdf63..d7f317176e 100644
--- a/esphome/core/hal/hal_host.h
+++ b/esphome/core/hal/hal_host.h
@@ -3,6 +3,7 @@
 #ifdef USE_HOST
 
 #include <cstdint>
+#include <sched.h>
 
 #define IRAM_ATTR
 #define PROGMEM
@@ -13,17 +14,18 @@ namespace esphome {
 /// Host has no ISR concept.
 __attribute__((always_inline)) inline bool in_isr_context() { return false; }
 
-void yield();
+__attribute__((always_inline)) inline void yield() { ::sched_yield(); }
+
 void delay(uint32_t ms);
 uint32_t micros();
 uint32_t millis();
 uint64_t millis_64();
-
 void delayMicroseconds(uint32_t us);  // NOLINT(readability-identifier-naming)
-void arch_feed_wdt();
 uint32_t arch_get_cpu_cycle_count();
-void arch_init();
-uint32_t arch_get_cpu_freq_hz();
+
+__attribute__((always_inline)) inline void arch_init() {}
+__attribute__((always_inline)) inline void arch_feed_wdt() {}
+__attribute__((always_inline)) inline uint32_t arch_get_cpu_freq_hz() { return 1000000000U; }
 
 }  // namespace esphome