diff --git a/src/freedombone-tests b/src/freedombone-tests
index 191e5ca9..83f07c81 100755
--- a/src/freedombone-tests
+++ b/src/freedombone-tests
@@ -74,6 +74,18 @@ function test_app_functions {
     done
 }
 
+function test_unique_onion_ports {
+    # test that some services are not assigned the same onion port
+    FILES=src/${PROJECT_NAME}-app-*
+    ports=$(grep -r "_ONION_PORT=" $FILES | awk -F ':' '{print $2}' | uniq | awk -F '=' '{print $2}')
+    unique_ports=$(grep -r "_ONION_PORT=" $FILES | awk -F ':' '{print $2}' | uniq | awk -F '=' '{print $2}' | uniq)
+    if [[ "$ports" != "$unique_ports" ]]; then
+        echo $'Some onion ports are clashing'
+        grep -r "_ONION_PORT=" $FILES | awk -F ':' '{print $2}' | uniq
+        exit 637252
+    fi
+}
+
 while [[ $# > 1 ]]
 do
     key="$1"
@@ -92,6 +104,7 @@ done
 echo $'Running tests'
 
 test_app_functions
+test_unique_onion_ports
 
 echo $'All tests passed'