diff --git a/esphome/core/__init__.py b/esphome/core/__init__.py
index 5ce968f20d..ad9844a3bf 100644
--- a/esphome/core/__init__.py
+++ b/esphome/core/__init__.py
@@ -693,12 +693,13 @@ class EsphomeCore:
         """Get the FNV-1a 32-bit hash of the config.
 
         The hash is computed lazily and cached for performance.
+        Uses sort_keys=True to ensure deterministic ordering.
         """
         if self._config_hash is None:
             from esphome import yaml_util
             from esphome.helpers import fnv1a_32bit_hash
 
-            config_str = yaml_util.dump(self.config, show_secrets=True)
+            config_str = yaml_util.dump(self.config, show_secrets=True, sort_keys=True)
             self._config_hash = fnv1a_32bit_hash(config_str)
         return self._config_hash
 
diff --git a/esphome/yaml_util.py b/esphome/yaml_util.py
index 359b72b48f..bba4bbf487 100644
--- a/esphome/yaml_util.py
+++ b/esphome/yaml_util.py
@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 from collections.abc import Callable
+from contextlib import suppress
 import functools
 import inspect
 from io import BytesIO, TextIOBase, TextIOWrapper
@@ -501,13 +502,17 @@ def _load_yaml_internal_with_type(
         loader.dispose()
 
 
-def dump(dict_, show_secrets=False):
+def dump(dict_, show_secrets=False, sort_keys=False):
     """Dump YAML to a string and remove null."""
     if show_secrets:
         _SECRET_VALUES.clear()
         _SECRET_CACHE.clear()
     return yaml.dump(
-        dict_, default_flow_style=False, allow_unicode=True, Dumper=ESPHomeDumper
+        dict_,
+        default_flow_style=False,
+        allow_unicode=True,
+        Dumper=ESPHomeDumper,
+        sort_keys=sort_keys,
     )
 
 
@@ -543,6 +548,9 @@ class ESPHomeDumper(yaml.SafeDumper):
         best_style = True
         if hasattr(mapping, "items"):
             mapping = list(mapping.items())
+        if self.sort_keys:
+            with suppress(TypeError):
+                mapping = sorted(mapping)
         for item_key, item_value in mapping:
             node_key = self.represent_data(item_key)
             node_value = self.represent_data(item_value)
diff --git a/tests/unit_tests/test_yaml_util.py b/tests/unit_tests/test_yaml_util.py
index eac0ceabb8..c8cb3e144f 100644
--- a/tests/unit_tests/test_yaml_util.py
+++ b/tests/unit_tests/test_yaml_util.py
@@ -278,3 +278,31 @@ def test_secret_values_tracking(fixture_path: Path) -> None:
     assert yaml_util._SECRET_VALUES["super_secret_wifi"] == "wifi_password"
     assert "0123456789abcdef" in yaml_util._SECRET_VALUES
     assert yaml_util._SECRET_VALUES["0123456789abcdef"] == "api_key"
+
+
+def test_dump_sort_keys() -> None:
+    """Test that dump with sort_keys=True produces sorted output."""
+    # Create a dict with unsorted keys
+    data = {
+        "zebra": 1,
+        "alpha": 2,
+        "nested": {
+            "z_key": "z_value",
+            "a_key": "a_value",
+        },
+    }
+
+    # Without sort_keys, keys are in insertion order
+    unsorted = yaml_util.dump(data, sort_keys=False)
+    lines_unsorted = unsorted.strip().split("\n")
+    # First key should be "zebra" (insertion order)
+    assert lines_unsorted[0].startswith("zebra:")
+
+    # With sort_keys, keys are alphabetically sorted
+    sorted_dump = yaml_util.dump(data, sort_keys=True)
+    lines_sorted = sorted_dump.strip().split("\n")
+    # First key should be "alpha" (alphabetical order)
+    assert lines_sorted[0].startswith("alpha:")
+    # nested keys should also be sorted
+    assert "a_key:" in sorted_dump
+    assert sorted_dump.index("a_key:") < sorted_dump.index("z_key:")