diff --git a/service/qos/qos_common.cc b/service/qos/qos_common.cc
index a56a8c5cf5..26be4391da 100644
--- a/service/qos/qos_common.cc
+++ b/service/qos/qos_common.cc
@@ -41,4 +41,22 @@ service_level_options service_level_options::replace_defaults(const service_leve
     return ret;
 }
 
+service_level_options service_level_options::merge_with(const service_level_options& other) const {
+    service_level_options ret = *this;
+    std::visit(overloaded_functor {
+        [&] (const unset_marker& um) {
+            ret.timeout = other.timeout;
+        },
+        [&] (const delete_marker& dm) {
+            ret.timeout = other.timeout;
+        },
+        [&] (const lowres_clock::duration& d) {
+            if (auto* other_timeout = std::get_if<lowres_clock::duration>(&other.timeout)) {
+                ret.timeout = std::min(d, *other_timeout);
+            }
+        },
+    }, ret.timeout);
+    return ret;
+}
+
 }
diff --git a/service/qos/qos_common.hh b/service/qos/qos_common.hh
index b4b79f8568..54845a17c5 100644
--- a/service/qos/qos_common.hh
+++ b/service/qos/qos_common.hh
@@ -49,6 +49,9 @@ struct service_level_options {
     timeout_type timeout = unset_marker{};
 
     service_level_options replace_defaults(const service_level_options& other) const;
+    // Merges the values of two service level options. The semantics depends
+    // on the type of the parameter - e.g. for timeouts, a min value is preferred.
+    service_level_options merge_with(const service_level_options& other) const;
 
     bool operator==(const service_level_options& other) const = default;
     bool operator!=(const service_level_options& other) const = default;