diff --git a/core/dbt/cli/option_types.py b/core/dbt/cli/option_types.py
index b90980840c0..006b28c7c19 100644
--- a/core/dbt/cli/option_types.py
+++ b/core/dbt/cli/option_types.py
@@ -1,5 +1,6 @@
 from typing import Optional
 
+import pytz
 from click import Choice, Context, Parameter, ParamType
 
 from dbt.config.utils import normalize_warn_error_options, parse_cli_yaml_string
@@ -104,7 +105,16 @@ def convert(
 
         if isinstance(value, str):
             try:
-                return SampleWindow.from_relative_string(value)
+                # Try and identify if it's a "dict" or a "str"
+                if value.lstrip()[0] == "{":
+                    param_option_name: str = param.opts[0] if param.opts else param.name  # type: ignore
+                    parsed_dict = parse_cli_yaml_string(value, param_option_name.strip("-"))
+                    sample_window = SampleWindow.from_dict(parsed_dict)
+                    sample_window.start = sample_window.start.replace(tzinfo=pytz.UTC)
+                    sample_window.end = sample_window.end.replace(tzinfo=pytz.UTC)
+                    return sample_window
+                else:
+                    return SampleWindow.from_relative_string(value)
             except Exception as e:
                 self.fail(e.__str__(), param, ctx)
         else:
diff --git a/tests/unit/cli/test_option_types.py b/tests/unit/cli/test_option_types.py
index 1067f64a3c3..bf43df8d13a 100644
--- a/tests/unit/cli/test_option_types.py
+++ b/tests/unit/cli/test_option_types.py
@@ -1,7 +1,13 @@
+from datetime import datetime
+from typing import Union
+
+import freezegun
 import pytest
+import pytz
 from click import BadParameter, Option
 
-from dbt.cli.option_types import YAML
+from dbt.cli.option_types import YAML, SampleWindowType
+from dbt.event_time.sample_window import SampleWindow
 
 
 class TestYAML:
@@ -24,3 +30,51 @@ def test_yaml_init_invalid_yaml_str(self, invalid_yaml_str):
         with pytest.raises(BadParameter) as e:
             YAML().convert(invalid_yaml_str, Option(["--vars"]), None)
         assert "--vars" in e.value.format_message()
+
+
+class TestSampleWindowType:
+    @pytest.mark.parametrize(
+        "input,expected_result",
+        [
+            (
+                "{'start': '2025-01-24', 'end': '2025-01-27'}",
+                SampleWindow(
+                    start=datetime(2025, 1, 24, 0, 0, 0, 0, pytz.UTC),
+                    end=datetime(2025, 1, 27, 0, 0, 0, 0, pytz.UTC),
+                ),
+            ),
+            (
+                "{'tart': '2025-01-24', 'bend': '2025-01-27'}",
+                BadParameter('Field "start" of type datetime is missing in SampleWindow instance'),
+            ),
+            (
+                "{}",
+                BadParameter('Field "start" of type datetime is missing in SampleWindow instance'),
+            ),
+            (
+                "cats",
+                BadParameter(
+                    "Runtime Error\n  Cannot load SAMPLE_WINDOW from 'cats'. Must be of form 'DAYS_INT GRAIN_SIZE'."
+                ),
+            ),
+        ],
+    )
+    def test_convert(self, input: str, expected_result: Union[SampleWindow, Exception]):
+        try:
+            result = SampleWindowType().convert(input, Option(["--sample-window"]), None)
+            assert result == expected_result
+        except Exception as e:
+            assert str(e) == str(expected_result)
+
+    # this had to be a seprate test case because the @freezegun.freeze_time
+    # was screwing up the instantiation of SampleWindow.from_dict calls for the
+    # other test cases
+    @freezegun.freeze_time("2025-01-28T02:03:0Z")
+    def test_convert_relative(self):
+        input = "3 days"
+        expected_result = SampleWindow(
+            start=datetime(2025, 1, 25, 2, 3, 0, 0, pytz.UTC),
+            end=datetime(2025, 1, 28, 2, 3, 0, 0, pytz.UTC),
+        )
+        result = SampleWindowType().convert(input, Option(["--sample-window"]), None)
+        assert result == expected_result