diff --git a/imagery/i.rectify/testsuite/test_i_rectify.py b/imagery/i.rectify/testsuite/test_i_rectify.py
new file mode 100644
index 00000000000..4de3283a4b7
--- /dev/null
+++ b/imagery/i.rectify/testsuite/test_i_rectify.py
@@ -0,0 +1,243 @@
+import os
+import tempfile
+from pathlib import Path
+from grass.gunittest.case import TestCase
+import grass.script as gs
+from grass.gunittest.main import test
+
+
+class TestIRectify(TestCase):
+    """Regression testsuite for i.rectify module."""
+
+    input_maps = ["rectify_band1", "rectify_band2"]
+    group = "test_rectify_group"
+    tmp_rasters = []
+    tmp_files = []
+
+    GCP_SETS = {
+        "affine": """\
+    1 1 1 1 1 1
+    9 1 9 1 1 1
+    1 9 1 9 1 1
+    9 9 9 9 1 1
+    5 5 5 5 1 1
+    """,
+        "order2": """\
+    1 1 1 1 1 1
+    1 5 1 5 1 1
+    1 9 1 9 1 1
+    3 2 3 2 1 1
+    3 7 3 7 1 1
+    5 5 5 5 1 1
+    """,
+        "order3": """\
+    1 1 1 1 1 1
+    1 5 1 5 1 1
+    1 9 1 9 1 1
+    3 2 3 2 1 1
+    3 7 3 7 1 1
+    5 1 5 1 1 1
+    5 5 5 5 1 1
+    5 9 5 9 1 1
+    7 2 7 2 1 1
+    7 8 7 8 1 1
+    9 1 9 1 1 1
+    9 9 9 9 1 1
+    """,
+    }
+
+    @classmethod
+    def setUpClass(cls):
+        """Set up input rasters, group, and target."""
+        cls.use_temp_region()
+        cls.runModule("g.region", n=10, s=0, e=10, w=0, res=1)
+
+        expressions = [
+            f"{cls.input_maps[0]} = row() + col()",
+            f"{cls.input_maps[1]} = row() * col()",
+        ]
+        for expr in expressions:
+            cls.runModule("r.mapcalc", expression=expr, overwrite=True)
+
+        cls.tmp_rasters.extend(cls.input_maps)
+        cls.runModule("i.group", group=cls.group, input=",".join(cls.input_maps))
+
+        env = gs.gisenv()
+        cls.group_path = os.path.join(
+            env["GISDBASE"], env["LOCATION_NAME"], env["MAPSET"], "group", cls.group
+        )
+        os.makedirs(cls.group_path, exist_ok=True)
+        cls.points_path = os.path.join(cls.group_path, "POINTS")
+        cls.runModule(
+            "i.target",
+            group=cls.group,
+            location=env["LOCATION_NAME"],
+            mapset=env["MAPSET"],
+        )
+
+    @classmethod
+    def set_control_points(cls, gcp_string):
+        """Helper to set control points for rectification."""
+        with tempfile.NamedTemporaryFile(mode="w", delete=False) as f:
+            f.write(gcp_string)
+            temp_path = f.name
+
+        cls.tmp_files.append(temp_path)
+        Path(temp_path).replace(cls.points_path)
+
+    @classmethod
+    def tearDownClass(cls):
+        """Remove input rasters, group, and temporary files."""
+        cls.runModule("g.remove", type="raster", name=cls.tmp_rasters, flags="f")
+        cls.runModule("g.remove", type="group", name=cls.group, flags="f")
+        if os.path.exists(cls.points_path):
+            os.remove(cls.points_path)
+        for f in cls.tmp_files:
+            if os.path.exists(f):
+                os.remove(f)
+
+    def _run_and_check(
+        self,
+        extension,
+        order,
+        method,
+        stats=None,
+        flags=None,
+        resolution=None,
+        single_input=False,
+        gcp_key=None,
+    ):
+        """Helper to run i.rectify and check the results."""
+        if gcp_key:
+            self.set_control_points(self.GCP_SETS[gcp_key])
+
+        inputs = self.input_maps[:1] if single_input else self.input_maps
+        args = {
+            "group": self.group,
+            "input": ",".join(inputs),
+            "extension": extension,
+            "order": order,
+            "method": method,
+        }
+        if resolution is not None:
+            args["resolution"] = resolution
+        if flags:
+            args["flags"] = flags
+
+        self.assertModule("i.rectify", **args)
+
+        for name in inputs:
+            rectified = f"{name}{extension}"
+            self.assertRasterExists(rectified)
+            self.tmp_rasters.append(rectified)
+            if stats:
+                self.assertRasterFitsUnivar(rectified, stats[rectified], precision=1e-6)
+
+    def test_affine_rectification(self):
+        """Validate affine transformation (order=1) using cubic interpolation."""
+
+        self._run_and_check(
+            "order1_poly",
+            1,
+            "cubic",
+            {
+                "rectify_band1order1_poly": {"mean": 10.0, "max": 16.0, "min": 4.0},
+                "rectify_band2order1_poly": {"mean": 25, "max": 64.0, "min": 4.0},
+            },
+            gcp_key="affine",
+        )
+
+    def test_polynomial_order2_rectification(self):
+        """Validate polynomial transformation of order 2 using linear interpolation."""
+        self._run_and_check(
+            "order2_poly",
+            2,
+            "linear",
+            {
+                "rectify_band1order2_poly": {"mean": 10.0},
+                "rectify_band2order2_poly": {"mean": 25.0},
+            },
+            gcp_key="order2",
+        )
+
+    def test_polynomial_order3_rectification(self):
+        """Validate polynomial transformation of order 3 using lanczos interpolation."""
+        self._run_and_check(
+            "order3_poly",
+            3,
+            "lanczos",
+            {
+                "rectify_band1order3_poly": {"mean": 11.0},
+                "rectify_band2order3_poly": {"mean": 30.25},
+            },
+            gcp_key="order3",
+        )
+
+    def test_region_restriction(self):
+        """Test output restriction to current region using 'c' flag."""
+        self.use_temp_region()
+        self.runModule("g.region", n=5, s=0, e=5, w=0, rows=5, cols=5)
+        self._run_and_check("cflag", 1, "nearest", flags="c", gcp_key="affine")
+        for name in self.input_maps:
+            rectified = f"{name}cflag"
+            info = gs.parse_command("r.info", map=rectified, format="json")
+            self.assertEqual(info["north"], 5.0)
+            self.assertEqual(info["south"], 0.0)
+            self.assertEqual(info["east"], 5.0)
+            self.assertEqual(info["west"], 0.0)
+        self.del_temp_region()
+
+    def test_c_flag_with_resolution_override(self):
+        """Test that 'c' flag overrides explicit resolution setting."""
+        self.use_temp_region()
+        self.runModule("g.region", n=5, s=0, e=5, w=0, res=5)
+        self._run_and_check(
+            "cflag_res", 1, "nearest", flags="c", resolution=2, gcp_key="affine"
+        )
+        for name in self.input_maps:
+            rectified = f"{name}cflag_res"
+            info = gs.parse_command("r.info", map=rectified, format="json")
+            self.assertEqual(info["nsres"], 5.0)
+            self.assertEqual(info["ewres"], 5.0)
+        self.del_temp_region()
+
+    def test_automatic_rectification(self):
+        """Test automatic rectification of all maps in the group using 'a' flag."""
+        self._run_and_check(
+            "auto",
+            1,
+            "cubic_f",
+            flags="a",
+            stats={
+                "rectify_band1auto": {"mean": 11.0, "max": 20.0, "min": 2.0},
+                "rectify_band2auto": {"mean": 30.25, "max": 100.0, "min": 1.0},
+            },
+            gcp_key="affine",
+        )
+
+    def test_thin_plate_spline(self):
+        """Test thin plate spline transformation using 't' flag."""
+        self._run_and_check(
+            "tps",
+            1,
+            "linear_f",
+            flags="t",
+            stats={
+                "rectify_band1tps": {"mean": 11.0},
+                "rectify_band2tps": {"mean": 30.25},
+            },
+            gcp_key="affine",
+        )
+
+    def test_resolution_parameter(self):
+        """Test explicit resolution parameter for output raster."""
+        self._run_and_check(
+            "res2", 1, "lanczos_f", resolution=2, single_input=True, gcp_key="affine"
+        )
+        info = gs.parse_command("r.info", map="rectify_band1res2", format="json")
+        self.assertEqual(info["nsres"], 2.0)
+        self.assertEqual(info["ewres"], 2.0)
+
+
+if __name__ == "__main__":
+    test()