diff --git a/src/config/ConfigManager.cpp b/src/config/ConfigManager.cpp
index 7a58ffcf..7b24263a 100644
--- a/src/config/ConfigManager.cpp
+++ b/src/config/ConfigManager.cpp
@@ -1562,6 +1562,11 @@ std::vector<SP<CWindowRule>> CConfigManager::getMatchingRules(PHLWINDOW pWindow,
                         continue;
                 }
 
+                if (rule->m_modal != -1) {
+                    if (rule->m_modal != pWindow->isModal())
+                        continue;
+                }
+
                 if (!rule->m_fullscreenState.empty()) {
                     const auto ARGS = CVarList(rule->m_fullscreenState, 2, ' ');
                     //
@@ -2735,6 +2740,8 @@ std::optional<std::string> CConfigManager::handleWindowRule(const std::string& c
             set |= (rule->m_focus = (v == "1"), true);
         if (auto v = get("group"); !v.empty())
             set |= (rule->m_group = (v == "1"), true);
+        if (auto v = get("modal"); !v.empty())
+            set |= (rule->m_modal = (v == "1"), true);
 
         if (auto v = get("fullscreenstate"); !v.empty())
             set |= (rule->m_fullscreenState = v, true);
@@ -2797,6 +2804,8 @@ std::optional<std::string> CConfigManager::handleWindowRule(const std::string& c
                     return false;
                 if (rule->m_group != -1 && rule->m_group != other->m_group)
                     return false;
+                if (rule->m_modal != -1 && rule->m_modal != other->m_modal)
+                    return false;
                 return true;
             });
         } else {
diff --git a/src/desktop/WindowRule.hpp b/src/desktop/WindowRule.hpp
index 2efeba0f..5bf462e9 100644
--- a/src/desktop/WindowRule.hpp
+++ b/src/desktop/WindowRule.hpp
@@ -60,6 +60,7 @@ class CWindowRule {
     int               m_pinned          = -1;
     int               m_focus           = -1;
     int               m_group           = -1;
+    int               m_modal           = -1;
     std::string       m_fullscreenState = ""; // empty means any
     std::string       m_onWorkspace     = ""; // empty means any
     std::string       m_workspace       = ""; // empty means any