diff --git a/esphome/components/packages/__init__.py b/esphome/components/packages/__init__.py
index 04db690c6f4..3a15b5b95a4 100644
--- a/esphome/components/packages/__init__.py
+++ b/esphome/components/packages/__init__.py
@@ -45,6 +45,18 @@ def is_remote_package(package_config: dict) -> bool:
     return CONF_URL in package_config
 
 
+def is_package_definition(value: object) -> bool:
+    """Returns True if the value looks like a package definition rather than a config fragment.
+
+    Package definitions are IncludeFile objects, git URL shorthand strings, or
+    remote package dicts (containing a ``url:`` key).  Config fragments are
+    plain dicts that represent component configuration.
+    """
+    return isinstance(value, (yaml_util.IncludeFile, str)) or (
+        isinstance(value, dict) and is_remote_package(value)
+    )
+
+
 def valid_package_contents(package_config: dict) -> dict:
     """Validate that a package looks like a plausible ESPHome config fragment.
 
@@ -318,11 +330,11 @@ def _walk_packages(
         if not isinstance(packages, dict):
             _walk_package_list(packages, callback, context)
         elif (result := _walk_package_dict(packages, callback, context)) is not None:
-            if not validate_deprecated:
+            if not validate_deprecated or any(
+                is_package_definition(v) for v in packages.values()
+            ):
                 raise result
             # Fallback: treat the dict as a single deprecated package.
-            # Note: this catches *any* cv.Invalid from the callback, which may
-            # mask real validation errors in named package dicts.
             # This block can be removed once the single-package
             # deprecation period (2026.7.0) is over.
             config[CONF_PACKAGES] = [packages]
@@ -461,6 +473,9 @@ class _PackageProcessor:
         self, package_config: dict | str, context_vars: ContextVars | None
     ) -> dict:
         """Resolve a single package and recurse into any nested packages."""
+        from_remote = isinstance(package_config, dict) and is_remote_package(
+            package_config
+        )
         package_config = self.resolve_package(package_config, context_vars)
         self.collect_substitutions(package_config)
 
@@ -470,7 +485,18 @@ class _PackageProcessor:
         # Push context from !include vars on the package root and on the packages key
         context_vars = push_context(package_config, context_vars)
         context_vars = push_context(package_config[CONF_PACKAGES], context_vars)
-        return _walk_packages(package_config, self.process_package, context_vars)
+        # Disable the deprecated single-package fallback for remote
+        # packages.  _process_remote_package returns dicts with
+        # already-resolved values that is_package_definition cannot
+        # distinguish from config fragments, so the fallback would
+        # always fire and mask real errors with wrong paths
+        # (packages->0 instead of packages-><name>).
+        return _walk_packages(
+            package_config,
+            self.process_package,
+            context_vars,
+            validate_deprecated=not from_remote,
+        )
 
 
 def do_packages_pass(
diff --git a/tests/component_tests/packages/test_packages.py b/tests/component_tests/packages/test_packages.py
index 0893c7dcbbc..0b828d757ed 100644
--- a/tests/component_tests/packages/test_packages.py
+++ b/tests/component_tests/packages/test_packages.py
@@ -1,11 +1,18 @@
 """Tests for the packages component."""
 
+import logging
 from pathlib import Path
 from unittest.mock import MagicMock, patch
 
 import pytest
 
-from esphome.components.packages import CONFIG_SCHEMA, do_packages_pass, merge_packages
+from esphome.components.packages import (
+    CONFIG_SCHEMA,
+    _walk_packages,
+    do_packages_pass,
+    is_package_definition,
+    merge_packages,
+)
 from esphome.components.substitutions import do_substitution_pass
 import esphome.config as config_module
 from esphome.config import resolve_extend_remove
@@ -37,7 +44,7 @@ from esphome.const import (
 )
 from esphome.core import CORE
 from esphome.util import OrderedDict
-from esphome.yaml_util import add_context
+from esphome.yaml_util import IncludeFile, add_context
 
 # Test strings
 TEST_DEVICE_NAME = "test_device_name"
@@ -79,6 +86,44 @@ def packages_pass(config):
     return config
 
 
+_INCLUDE_FILE = "INCLUDE_FILE"
+
+
+@pytest.mark.parametrize(
+    ("value", "expected"),
+    [
+        # IncludeFile objects are package definitions
+        (_INCLUDE_FILE, True),
+        # Git URL shorthand strings are package definitions
+        ("github://esphome/firmware/base.yaml@main", True),
+        # Remote package dicts (with url key) are package definitions
+        ({"url": "https://github.com/esphome/firmware", "file": "base.yaml"}, True),
+        # Plain config dicts are NOT package definitions (they are config fragments)
+        ({"wifi": {"ssid": "test"}}, False),
+        # None is not a package definition
+        (None, False),
+        # Lists are not package definitions
+        ([{"wifi": {"ssid": "test"}}], False),
+        # Empty dicts are not package definitions
+        ({}, False),
+    ],
+    ids=[
+        "include_file",
+        "git_shorthand",
+        "remote_package",
+        "config_fragment",
+        "none",
+        "list",
+        "empty_dict",
+    ],
+)
+def test_is_package_definition(value: object, expected: bool) -> None:
+    """Test that is_package_definition correctly identifies package definitions."""
+    if value is _INCLUDE_FILE:
+        value = MagicMock(spec=IncludeFile)
+    assert is_package_definition(value) is expected
+
+
 def test_package_unused(basic_esphome, basic_wifi) -> None:
     """
     Ensures do_package_pass does not change a config if packages aren't used.
@@ -1107,6 +1152,134 @@ def test_invalid_package_contents_masked_by_deprecation(
         do_packages_pass(config)
 
 
+def test_named_dict_with_include_files_no_false_deprecation_warning(
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """Package errors in named dicts must not trigger the deprecated fallback."""
+    good_include = MagicMock(spec=IncludeFile)
+    bad_include = MagicMock(spec=IncludeFile)
+
+    config = {
+        CONF_PACKAGES: {
+            "good_pkg": good_include,
+            "bad_pkg": bad_include,
+        },
+    }
+
+    call_count = 0
+
+    def failing_callback(package_config: dict, context: object) -> dict:
+        nonlocal call_count
+        call_count += 1
+        if call_count == 1:
+            # First package processes fine
+            return {CONF_WIFI: {CONF_SSID: "test"}}
+        # Second package has an error (e.g. jinja syntax error)
+        raise cv.Invalid("simulated jinja error in bad_pkg")
+
+    with (
+        caplog.at_level(logging.WARNING),
+        pytest.raises(cv.Invalid, match="simulated jinja error"),
+    ):
+        _walk_packages(config, failing_callback)
+
+    # Must NOT emit the deprecated single-package warning
+    assert "deprecated" not in caplog.text.lower()
+
+
+def test_validate_deprecated_false_raises_directly(
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """With validate_deprecated=False, errors raise directly without fallback.
+
+    This is the codepath used for remote packages where _process_remote_package
+    returns already-resolved dicts that is_package_definition cannot detect.
+    """
+    config = {
+        CONF_PACKAGES: {
+            "pkg_a": {CONF_WIFI: {CONF_SSID: "test"}},
+            "pkg_b": {CONF_WIFI: {CONF_SSID: "test2"}},
+        },
+    }
+
+    call_count = 0
+
+    def failing_callback(package_config: dict, context: object) -> dict:
+        nonlocal call_count
+        call_count += 1
+        if call_count == 1:
+            return package_config
+        raise cv.Invalid("nested error")
+
+    with (
+        caplog.at_level(logging.WARNING),
+        pytest.raises(cv.Invalid, match="nested error"),
+    ):
+        _walk_packages(config, failing_callback, validate_deprecated=False)
+
+    assert "deprecated" not in caplog.text.lower()
+
+
+def test_error_on_first_declared_package_still_detected() -> None:
+    """When the first declared package errors, it's the last processed in reverse.
+
+    All other entries are already resolved to dicts, but the failing entry
+    retains its original IncludeFile value since assignment was skipped.
+    """
+    config = {
+        CONF_PACKAGES: {
+            "first_pkg": MagicMock(spec=IncludeFile),
+            "second_pkg": MagicMock(spec=IncludeFile),
+            "third_pkg": MagicMock(spec=IncludeFile),
+        },
+    }
+
+    call_count = 0
+
+    def fail_on_last(package_config: dict, context: object) -> dict:
+        nonlocal call_count
+        call_count += 1
+        # Reverse iteration: third_pkg (1), second_pkg (2), first_pkg (3)
+        if call_count < 3:
+            return {CONF_WIFI: {CONF_SSID: "test"}}
+        raise cv.Invalid("error in first_pkg")
+
+    with pytest.raises(cv.Invalid, match="error in first_pkg"):
+        _walk_packages(config, fail_on_last)
+
+
+def test_deprecated_single_package_fallback_still_works(
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """The deprecated single-package form still falls back at the top level.
+
+    When a dict's values are plain config fragments (not package definitions)
+    and the callback fails, the deprecated fallback wraps the dict in a list
+    and retries with a deprecation warning.
+    """
+    config = {
+        CONF_PACKAGES: {
+            CONF_WIFI: {CONF_SSID: "test", CONF_PASSWORD: "secret"},
+        },
+    }
+
+    attempt = 0
+
+    def fail_then_succeed(package_config: dict, context: object) -> dict:
+        nonlocal attempt
+        attempt += 1
+        if attempt == 1:
+            # First attempt: treating as named dict fails
+            raise cv.Invalid("not a valid package")
+        # Second attempt: after fallback wraps as list, succeeds
+        return package_config
+
+    with caplog.at_level(logging.WARNING):
+        _walk_packages(config, fail_then_succeed)
+
+    assert "deprecated" in caplog.text.lower()
+
+
 def test_merge_packages_invalid_nested_type_raises() -> None:
     """Invalid nested packages type during merge raises cv.Invalid."""
     config = {