diff --git a/atlas/templates/atlas/partials/case_search_widget.html b/atlas/templates/atlas/partials/case_search_widget.html
index ec1a3ca5..f5d47134 100644
--- a/atlas/templates/atlas/partials/case_search_widget.html
+++ b/atlas/templates/atlas/partials/case_search_widget.html
@@ -2,7 +2,9 @@
   <label for="case-search-input" class="form-label">Search cases</label>
   <input id="case-search-input" name="q" class="form-control" type="search"
     placeholder="Type to search cases..."
-    hx-get="{% url 'atlas:case_search' %}?collection={{ collection.pk }}"
+    hx-get="{% url 'atlas:case_search' %}"
+    hx-include="#case-search-input"
+    hx-vals='{"collection": "{{ collection.pk }}"}'
     hx-target="#case-search-results"
     hx-trigger="keyup changed delay:400ms"
     autocomplete="off">