diff --git a/homeassistant/components/image/__init__.py b/homeassistant/components/image/__init__.py
index dbb5962eabf..ea235127894 100644
--- a/homeassistant/components/image/__init__.py
+++ b/homeassistant/components/image/__init__.py
@@ -348,7 +348,7 @@ async def async_get_still_stream(
         # While this results in additional bandwidth usage,
         # given the low frequency of image updates, it is acceptable.
         frame.extend(frame)
-        await response.write(frame)
+        await response.write(frame)  # type: ignore[arg-type]
         return True
 
     event = asyncio.Event()
diff --git a/mypy.ini b/mypy.ini
index e76bc97585c..15b96e0a802 100644
--- a/mypy.ini
+++ b/mypy.ini
@@ -10,6 +10,7 @@ show_error_codes = true
 follow_imports = normal
 local_partial_types = true
 strict_equality = true
+strict_bytes = true
 no_implicit_optional = true
 warn_incomplete_stub = true
 warn_redundant_casts = true
diff --git a/requirements_test.txt b/requirements_test.txt
index 50e5957bf96..98a948cd56e 100644
--- a/requirements_test.txt
+++ b/requirements_test.txt
@@ -12,7 +12,7 @@ coverage==7.6.8
 freezegun==1.5.1
 license-expression==30.4.0
 mock-open==1.4.0
-mypy-dev==1.14.0a6
+mypy-dev==1.14.0a7
 pre-commit==4.0.0
 pydantic==2.10.3
 pylint==3.3.2
diff --git a/script/hassfest/mypy_config.py b/script/hassfest/mypy_config.py
index 5767066c943..1d7f2b5ed88 100644
--- a/script/hassfest/mypy_config.py
+++ b/script/hassfest/mypy_config.py
@@ -47,6 +47,7 @@ GENERAL_SETTINGS: Final[dict[str, str]] = {
     # Enable some checks globally.
     "local_partial_types": "true",
     "strict_equality": "true",
+    "strict_bytes": "true",
     "no_implicit_optional": "true",
     "warn_incomplete_stub": "true",
     "warn_redundant_casts": "true",