diff --git a/server/extension/expected/40_admin1_test.out b/server/extension/expected/40_admin1_test.out
new file mode 100644
index 0000000..dc7a839
--- /dev/null
+++ b/server/extension/expected/40_admin1_test.out
@@ -0,0 +1,22 @@
+-- Check that the public function is callable, even with no data
+-- It should return NULL
+SELECT cdb_geocoder_server.geocode_admin1_polygons(session_user, txid_current(), 'California');
+ geocode_admin1_polygons 
+-------------------------
+ 
+(1 row)
+
+-- Insert some dummy data and geometry to return
+INSERT INTO global_province_polygons (synonyms, the_geom) VALUES (Array['Califonia'], ST_GeomFromText(
+  'POLYGON((-71.1031880899493 42.3152774590236,
+            -71.1031627617667 42.3152960829043,
+            -71.102923838298 42.3149156848307,
+            -71.1031880899493 42.3152774590236))',4326)
+);
+-- This should return the polygon inserted above
+SELECT cdb_geocoder_server.geocode_admin1_polygons(session_user, txid_current(), 'California');
+ geocode_admin1_polygons 
+-------------------------
+ 
+(1 row)
+
diff --git a/server/extension/sql/0.0.1/40_admin1.sql b/server/extension/sql/0.0.1/40_admin1.sql
new file mode 100644
index 0000000..c8d351d
--- /dev/null
+++ b/server/extension/sql/0.0.1/40_admin1.sql
@@ -0,0 +1,50 @@
+-- Interface of the server extension
+
+CREATE OR REPLACE FUNCTION geocode_admin1_polygons(user_id name, tx_id bigint, admin1_name text)
+RETURNS Geometry AS $$
+    plpy.debug('Entering geocode_admin1_polygons')
+    plpy.debug('user_id = %s' % user_id)
+
+    #-- Access control
+    #-- TODO: this should be part of cdb python library
+    if user_id == 'publicuser':
+        plpy.error('The api_key must be provided')
+
+    #--TODO: rate limiting check
+    #--TODO: quota check
+
+    #-- Copied from the doc, see http://www.postgresql.org/docs/9.4/static/plpython-database.html
+    plan = plpy.prepare("SELECT cdb_geocoder_server._geocode_admin1_polygons($1) AS mypolygon", ["text"])
+    rv = plpy.execute(plan, [admin1_name], 1)
+
+    plpy.debug('Returning from Returning from geocode_admin1_polygons')
+    return rv[0]["mypolygon"]
+$$ LANGUAGE plpythonu;
+
+
+--------------------------------------------------------------------------------
+
+-- Implementation of the server extension
+-- Note: these functions depend on the cdb_geocoder extension
+CREATE OR REPLACE FUNCTION _geocode_admin1_polygons(admin1_name text)
+RETURNS Geometry AS $$
+  DECLARE
+    ret Geometry;
+  BEGIN
+    SELECT geom INTO ret
+    FROM (
+      SELECT q, (
+          SELECT the_geom 
+          FROM global_province_polygons
+          WHERE d.c = ANY (synonyms) 
+          ORDER BY frequency DESC LIMIT 1
+        ) geom
+      FROM (
+        SELECT 
+          trim(replace(lower(admin1_name),'.',' ')) c, admin1_name q
+        ) d
+      ) v;
+
+    RETURN ret;
+  END
+$$ LANGUAGE plpgsql;
diff --git a/server/extension/sql/40_admin1_test.sql b/server/extension/sql/40_admin1_test.sql
new file mode 100644
index 0000000..e96cbfc
--- /dev/null
+++ b/server/extension/sql/40_admin1_test.sql
@@ -0,0 +1,14 @@
+-- Check that the public function is callable, even with no data
+-- It should return NULL
+SELECT cdb_geocoder_server.geocode_admin1_polygons(session_user, txid_current(), 'California');
+
+-- Insert some dummy data and geometry to return
+INSERT INTO global_province_polygons (synonyms, the_geom) VALUES (Array['Califonia'], ST_GeomFromText(
+  'POLYGON((-71.1031880899493 42.3152774590236,
+            -71.1031627617667 42.3152960829043,
+            -71.102923838298 42.3149156848307,
+            -71.1031880899493 42.3152774590236))',4326)
+);
+
+-- This should return the polygon inserted above
+SELECT cdb_geocoder_server.geocode_admin1_polygons(session_user, txid_current(), 'California');