diff --git a/.gitignore b/.gitignore
index 48140f8..d46794c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -167,4 +167,6 @@ cython_debug/
 testing_wip.py
 
 # Output csv files
-*.csv
\ No newline at end of file
+a.csv
+b.csv
+c.csv
\ No newline at end of file
diff --git a/src/neighbourhood.py b/src/neighbourhood.py
index 703c57d..e957329 100644
--- a/src/neighbourhood.py
+++ b/src/neighbourhood.py
@@ -18,17 +18,6 @@ class ReportingNeighbourhoods:
     neighbourhood_id_to_reporting_unit_ids: Dict[str, Set[str]]
     neighbourhood_id_to_reference_group: Dict[str, ReportingUnitInfo]
 
-    def get_reference_group(
-        self, reporting_unit_id: str
-    ) -> Optional[ReportingUnitInfo]:
-        neighbourhood_id = self.reporting_unit_id_to_neighbourhood_id.get(
-            reporting_unit_id
-        )
-        if neighbourhood_id is None:
-            return None
-
-        return self.neighbourhood_id_to_reference_group[neighbourhood_id]
-
 
 class NeighbourhoodData:
     data: pl.LazyFrame
diff --git a/test/data/neighbourhood_files/invalid.csv b/test/data/neighbourhood_files/invalid.csv
new file mode 100644
index 0000000..83db119
--- /dev/null
+++ b/test/data/neighbourhood_files/invalid.csv
@@ -0,0 +1,2 @@
+neighbourhood_code,ambiguous
+123,no
\ No newline at end of file
diff --git a/test/data/neighbourhood_files/valid.csv b/test/data/neighbourhood_files/valid.csv
new file mode 100644
index 0000000..c0f0788
--- /dev/null
+++ b/test/data/neighbourhood_files/valid.csv
@@ -0,0 +1,3 @@
+zip_code,neighbourhood_code,ambiguous
+1234AB,WK123,no
+1235AB,WK123,no
\ No newline at end of file
diff --git a/test/data/neighbourhood_files/valid.parquet b/test/data/neighbourhood_files/valid.parquet
new file mode 100644
index 0000000..9467055
Binary files /dev/null and b/test/data/neighbourhood_files/valid.parquet differ
diff --git a/test/data/neighbourhood_files/wrong_filetype.txt b/test/data/neighbourhood_files/wrong_filetype.txt
new file mode 100644
index 0000000..e69de29
diff --git a/test/test_neighbourhood.py b/test/test_neighbourhood.py
new file mode 100644
index 0000000..c7dac34
--- /dev/null
+++ b/test/test_neighbourhood.py
@@ -0,0 +1,141 @@
+import pytest
+from eml_types import CandidateIdentifier, PartyIdentifier, ReportingUnitInfo
+from neighbourhood import NeighbourhoodData, ReportingNeighbourhoods
+from typing import Optional, Dict
+
+read_test_cases = [
+    ("./test/data/neighbourhood_files/valid.parquet", True),
+    ("./test/data/neighbourhood_files/valid.csv", True),
+    ("./test/data/neighbourhood_files/THIS_FILE_DOES_NOT_EXIST.parquet", False),
+    ("./test/data/THIS_FOLDER_DOES_NOT_EXIST/valid.parquet", False),
+    ("./test/data/neighbourhood_files/wrong_filetype.txt", False),
+    ("./test/data/neighbourhood_files/invalid.csv", False),
+]
+
+
+@pytest.mark.parametrize("path_to_read, should_load", read_test_cases)
+def test_read_neighbourhood_file(path_to_read: str, should_load: bool) -> None:
+    result = NeighbourhoodData.from_path(path_to_read)
+    if should_load:
+        assert isinstance(result, NeighbourhoodData)
+    else:
+        assert result is None
+
+
+fetch_test_cases = [
+    ("./test/data/neighbourhood_files/valid.csv", "1234AB", "WK123"),
+    ("./test/data/neighbourhood_files/valid.csv", "1235AB", "WK123"),
+    ("./test/data/neighbourhood_files/valid.csv", "1234AC", None),
+]
+
+
+@pytest.mark.parametrize("path_to_read, zip_code, expected", fetch_test_cases)
+def test_fetch_neighbourhood_code(
+    path_to_read: str, zip_code: str, expected: str
+) -> None:
+    data = NeighbourhoodData.from_path(path_to_read)
+    assert data is not None and data.fetch_neighbourhood_code(zip_code) == expected
+
+
+reporting_neighbourhoods_test_cases = [
+    (
+        "./test/data/neighbourhood_files/valid.csv",
+        {"SB1": "1234AB", "SB2": "1235AB", "SB3": "9999XX", "SB4": None},
+        {
+            "SB1": ReportingUnitInfo(
+                reporting_unit_id="SB1",
+                reporting_unit_name="SB1",
+                cast=0,
+                total_counted=0,
+                rejected_votes={},
+                uncounted_votes={},
+                votes_per_party={PartyIdentifier(id=1, name=None): 10},
+                votes_per_candidate={
+                    CandidateIdentifier(PartyIdentifier(id=1, name=None), 1): 8,
+                    CandidateIdentifier(PartyIdentifier(id=1, name=None), 2): 2,
+                },
+            ),
+            "SB2": ReportingUnitInfo(
+                reporting_unit_id="SB2",
+                reporting_unit_name="SB2",
+                cast=0,
+                total_counted=0,
+                rejected_votes={},
+                uncounted_votes={},
+                votes_per_party={PartyIdentifier(id=1, name=None): 12},
+                votes_per_candidate={
+                    CandidateIdentifier(PartyIdentifier(id=1, name=None), 1): 11,
+                    CandidateIdentifier(PartyIdentifier(id=1, name=None), 2): 1,
+                },
+            ),
+            "SB3": ReportingUnitInfo(
+                reporting_unit_id="SB3",
+                reporting_unit_name="SB3",
+                cast=0,
+                total_counted=0,
+                rejected_votes={},
+                uncounted_votes={},
+                votes_per_party={PartyIdentifier(id=1, name=None): 100},
+                votes_per_candidate={
+                    CandidateIdentifier(PartyIdentifier(id=1, name=None), 1): 80,
+                    CandidateIdentifier(PartyIdentifier(id=1, name=None), 2): 20,
+                },
+            ),
+            "SB4": ReportingUnitInfo(
+                reporting_unit_id="SB4",
+                reporting_unit_name="SB4",
+                cast=0,
+                total_counted=0,
+                rejected_votes={},
+                uncounted_votes={},
+                votes_per_party={PartyIdentifier(id=1, name=None): 200},
+                votes_per_candidate={
+                    CandidateIdentifier(PartyIdentifier(id=1, name=None), 1): 160,
+                    CandidateIdentifier(PartyIdentifier(id=1, name=None), 2): 40,
+                },
+            ),
+        },
+        ReportingNeighbourhoods(
+            reporting_unit_id_to_neighbourhood_id={
+                "SB1": "WK123",
+                "SB2": "WK123",
+                "SB3": None,
+                "SB4": None,
+            },
+            neighbourhood_id_to_reporting_unit_ids={"WK123": set(["SB1", "SB2"])},
+            neighbourhood_id_to_reference_group={
+                "WK123": ReportingUnitInfo(
+                    reporting_unit_id="WK123",
+                    reporting_unit_name=f"Reference group for WK123",
+                    cast=0,
+                    total_counted=0,
+                    rejected_votes={},
+                    uncounted_votes={},
+                    votes_per_party={PartyIdentifier(id=1, name=None): 22},
+                    votes_per_candidate={
+                        CandidateIdentifier(PartyIdentifier(id=1, name=None), 1): 19,
+                        CandidateIdentifier(PartyIdentifier(id=1, name=None), 2): 3,
+                    },
+                )
+            },
+        ),
+    )
+]
+
+
+@pytest.mark.parametrize(
+    "path_to_read, reporting_unit_zips, reporting_unit_info, expected",
+    reporting_neighbourhoods_test_cases,
+)
+def test_fetch_reporting_neighbourhoods(
+    path_to_read: str,
+    reporting_unit_zips: Dict[str, Optional[str]],
+    reporting_unit_info: Dict[str, ReportingUnitInfo],
+    expected: ReportingNeighbourhoods,
+) -> None:
+    neighbourhood_data = NeighbourhoodData.from_path(path_to_read)
+    assert neighbourhood_data is not None
+    reporting_neighourhoods = neighbourhood_data.fetch_reporting_neighbourhoods(
+        reporting_unit_zips, reporting_unit_info
+    )
+    assert reporting_neighourhoods == expected