diff --git a/esphome/espidf/bootloader.py b/esphome/espidf/bootloader.py
index 7ef6561f448..99a5ed15952 100644
--- a/esphome/espidf/bootloader.py
+++ b/esphome/espidf/bootloader.py
@@ -73,6 +73,11 @@ def _compute_enabled() -> bool:
             # The last configure saw a component customizing the bootloader.
             _LOGGER.info("Bootloader cache off: build customizes the bootloader")
             return False
+        resolved = toolchain._load_sdkconfig_json(toolchain._build_dir())
+        if resolved is not None and _resolved_blocks_cache(resolved):
+            # Hand edits to the real sdkconfig survive snapshot preservation.
+            _LOGGER.info("Bootloader cache off: secure options in the tree")
+            return False
         if not os.access(tools := framework.get_idf_tools_path(), os.W_OK):
             # A read-only shared prefix would fail the cache on every build.
             _LOGGER.info("Bootloader cache off: %s is not writable", tools)
@@ -120,6 +125,20 @@ def _snapshot_blocks_cache(sdkconfig_path: Path) -> bool:
     return config.get("CONFIG_APP_REPRODUCIBLE_BUILD", "") in _DISABLED_VALUES
 
 
+def _resolved_blocks_cache(app_config: dict) -> bool:
+    """Secure options in the resolved config; catches hand-edited sdkconfigs.
+
+    Key files are inputs the cache key cannot hash; *_SUPPORTED capability
+    constants are always on and say nothing about what is enabled.
+    """
+    return any(
+        name.startswith(("SECURE_", "FLASH_ENCRYPTION"))
+        and not name.endswith("_SUPPORTED")
+        and bool(value)
+        for name, value in app_config.items()
+    )
+
+
 def tree_uses_cached_bootloader(build_dir: Path) -> bool:
     """Whether a configured tree was set up for the cached bootloader."""
     cmakecache = build_dir / "CMakeCache.txt"
@@ -387,6 +406,10 @@ def ensure_cached_bootloader(verbose: bool = False) -> bool:
             _LOGGER.info("Bootloader customized by the build; building in-tree")
             return False
         app_config = toolchain._load_sdkconfig_json(toolchain._build_dir())
+        if app_config is not None and _resolved_blocks_cache(app_config):
+            # Configure just resolved a secure option the snapshot cannot see.
+            _LOGGER.info("Secure options in the resolved config; building in-tree")
+            return False
         offset = _bootloader_offset(app_config)
         table_offset = (app_config or {}).get("PARTITION_TABLE_OFFSET")
         compiler = toolchain._resolved_c_compiler()
diff --git a/tests/unit_tests/test_espidf_bootloader.py b/tests/unit_tests/test_espidf_bootloader.py
index 2efff1215d1..9ae1cb90c47 100644
--- a/tests/unit_tests/test_espidf_bootloader.py
+++ b/tests/unit_tests/test_espidf_bootloader.py
@@ -125,6 +125,35 @@ def test_enabled_project_bootloader_components_disable(tmp_path: Path) -> None:
         assert bootloader._compute_enabled() is False
 
 
+@pytest.mark.parametrize(
+    ("config", "blocks"),
+    [
+        ({"SECURE_BOOT": True}, True),
+        ({"SECURE_BOOT_SIGNING_KEY": "keys/sb.pem"}, True),
+        ({"FLASH_ENCRYPTION_ENABLED": True}, True),
+        ({"SECURE_BOOT_V1_SUPPORTED": True, "SECURE_BOOT": False}, False),
+        ({"A": "1"}, False),
+    ],
+    ids=["secure-boot", "signing-key", "flash-enc", "capability-only", "plain"],
+)
+def test_resolved_blocks_cache(config: dict, blocks: bool) -> None:
+    """Key file contents are inputs the key cannot hash; capabilities are not."""
+    assert bootloader._resolved_blocks_cache(config) is blocks
+
+
+def test_enabled_resolved_secure_option_disables(tmp_path: Path) -> None:
+    """A menuconfig edit to the real sdkconfig never reaches the snapshot."""
+    _write_snapshot("CONFIG_APP_REPRODUCIBLE_BUILD=y\n")
+    config_dir = toolchain._build_dir() / "config"
+    config_dir.mkdir(parents=True, exist_ok=True)
+    (config_dir / "sdkconfig.json").write_text('{"SECURE_BOOT": true}')
+    with (
+        _tools_prefix(tmp_path),
+        patch.object(build_gen, "idf_macro_matches", return_value=True),
+    ):
+        assert bootloader._compute_enabled() is False
+
+
 def test_enabled_recorded_bootloader_hooks_disable(tmp_path: Path) -> None:
     """A customization recorded by the last configure is an unseen input."""
     _write_snapshot("CONFIG_APP_REPRODUCIBLE_BUILD=y\n")
@@ -572,6 +601,20 @@ def test_ensure_rechecks_recorded_hooks_after_configure(tmp_path: Path) -> None:
     mock_build.assert_not_called()
 
 
+def test_ensure_bypasses_a_resolved_secure_option(tmp_path: Path) -> None:
+    """Configure resolves hand-edited secure options the snapshot cannot see."""
+    with (
+        _orchestration_env(tmp_path),
+        patch.object(bootloader, "_build_standalone") as mock_build,
+    ):
+        build = CORE.relative_build_path("build")
+        (build / "config" / "sdkconfig.json").write_text(
+            '{"SECURE_BOOT_SIGNING_KEY": "sb.pem"}'
+        )
+        assert bootloader.ensure_cached_bootloader() is False
+    mock_build.assert_not_called()
+
+
 def test_ensure_fails_soft_without_a_hooks_record(tmp_path: Path) -> None:
     """A configure that wrote no record cannot prove the bootloader is stock."""
     with (