diff --git a/src/pages/observatoire.py b/src/pages/observatoire.py
index d48518c..67ab659 100644
--- a/src/pages/observatoire.py
+++ b/src/pages/observatoire.py
@@ -1,9 +1,21 @@
+import urllib.parse
 from datetime import datetime, timedelta
 
 import dash_bootstrap_components as dbc
 import polars as pl
 import polars.selectors as cs
-from dash import ALL, Input, Output, State, callback, ctx, dcc, html, register_page
+from dash import (
+    ALL,
+    Input,
+    Output,
+    State,
+    callback,
+    ctx,
+    dcc,
+    html,
+    no_update,
+    register_page,
+)
 
 from src.figures import (
     get_barchart_sources,
@@ -107,7 +119,7 @@ def _apply_filters(
 
 layout = [
     dcc.Store(id="dashboard-filters"),
-    dcc.Location(id="dashboard_url"),
+    dcc.Location(id="dashboard_url", refresh="callback-nav"),
     dbc.Modal(
         [
             dbc.ModalHeader(dbc.ModalTitle("Montants")),
@@ -280,6 +292,24 @@ Alors, on fait comment ?
 ]
 
 
+@callback(
+    Output("dashboard_acheteur_id", "value"),
+    Output("dashboard_titulaire_id", "value"),
+    Output("dashboard_url", "search"),
+    Input("dashboard_url", "search"),
+)
+def restore_filters_from_url(search):
+    if not search:
+        return no_update, no_update, no_update
+
+    params = urllib.parse.parse_qs(search.lstrip("?"))
+
+    acheteur_id = params.get("acheteur_id", [None])[0] or no_update
+    titulaire_id = params.get("titulaire_id", [None])[0] or no_update
+
+    return acheteur_id, titulaire_id, ""
+
+
 @callback(
     Output("cards", "children"),
     Output("btn-download-observatoire", "disabled"),
diff --git a/tests/conftest.py b/tests/conftest.py
index b14e0f8..f0f2b00 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -34,6 +34,11 @@ def test_data():
             "sourceFile": "test.xml",
             "sourceDataset": "test_dataset",
             "datePublicationDonnees": datetime.date(2025, 1, 1),
+            "considerationsSociales": "",
+            "considerationsEnvironnementales": "",
+            "type": "Marché",
+            "acheteur_categorie": "Collectivité",
+            "titulaire_categorie": "PME",
         }
     ]
     path = "tests/test.parquet"
diff --git a/tests/test_main.py b/tests/test_main.py
index e3f77bb..995a669 100644
--- a/tests/test_main.py
+++ b/tests/test_main.py
@@ -137,3 +137,23 @@ def test_005_add_links_observatoire_titulaire():
 
     # titulaire_id should NOT contain observatoire link
     assert "/observatoire" not in id_value
+
+
+def test_006_observatoire_url_to_input(dash_duo: DashComposite):
+    from src.app import app
+
+    dash_duo.start_server(app)
+    dash_duo.wait_for_text_to_equal(".logo > h1", "decp.info", timeout=4)
+
+    # Navigate to observatoire with acheteur_id query param
+    dash_duo.wait_for_page(f"{dash_duo.server_url}/observatoire?acheteur_id=a1")
+    dash_duo.wait_for_element("#dashboard_acheteur_id", timeout=4)
+
+    import time
+
+    time.sleep(1)  # Allow callback chain to complete
+
+    acheteur_input = dash_duo.find_element("#dashboard_acheteur_id")
+    assert acheteur_input.get_attribute("value") == "a1", (
+        "acheteur_id input should be populated from URL param"
+    )