diff --git a/Framework/Core/CMakeLists.txt b/Framework/Core/CMakeLists.txt
index 1aed1f776b775..cefb903c29895 100644
--- a/Framework/Core/CMakeLists.txt
+++ b/Framework/Core/CMakeLists.txt
@@ -237,6 +237,7 @@ add_executable(o2-test-framework-core
               test/test_InputSpec.cxx
               test/test_LogParsingHelpers.cxx
               test/test_Mermaid.cxx
+              test/test_MessageSet.cxx
               test/test_OptionsHelpers.cxx
               test/test_OverrideLabels.cxx
               test/test_O2DataModelHelpers.cxx
diff --git a/Framework/Core/test/test_MessageSet.cxx b/Framework/Core/test/test_MessageSet.cxx
new file mode 100644
index 0000000000000..373cd7c8e5115
--- /dev/null
+++ b/Framework/Core/test/test_MessageSet.cxx
@@ -0,0 +1,95 @@
+// Copyright 2019-2025 CERN and copyright holders of ALICE O2.
+// See https://alice-o2.web.cern.ch/copyright for details of the copyright holders.
+// All rights not expressly granted are reserved.
+//
+// This software is distributed under the terms of the GNU General Public
+// License v3 (GPL Version 3), copied verbatim in the file "COPYING".
+//
+// In applying this license CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+#include <fairmq/Message.h>
+#include "Framework/MessageSet.h"
+#include <catch_amalgamated.hpp>
+
+using namespace o2::framework;
+
+TEST_CASE("MessageSet") {
+  o2::framework::MessageSet msgSet;
+  std::vector<fair::mq::MessagePtr> ptrs;
+  std::unique_ptr<fair::mq::Message> msg(nullptr);
+  std::unique_ptr<fair::mq::Message> msg2(nullptr);
+  ptrs.emplace_back(std::move(msg));
+  ptrs.emplace_back(std::move(msg2));
+  msgSet.add([&ptrs](size_t i) -> fair::mq::MessagePtr& { return ptrs[i]; }, 2);
+
+  REQUIRE(msgSet.messages.size() == 2);
+  REQUIRE(msgSet.messageMap.size() == 1);
+  REQUIRE(msgSet.pairMap.size() == 1);
+  REQUIRE(msgSet.messageMap[0].position == 0);
+  REQUIRE(msgSet.messageMap[0].size == 1);
+
+  REQUIRE(msgSet.pairMap[0].partIndex == 0);
+  REQUIRE(msgSet.pairMap[0].payloadIndex == 0);
+}
+
+TEST_CASE("MessageSetWithFunction") {
+  std::vector<fair::mq::MessagePtr> ptrs;
+  std::unique_ptr<fair::mq::Message> msg(nullptr);
+  std::unique_ptr<fair::mq::Message> msg2(nullptr);
+  ptrs.emplace_back(std::move(msg));
+  ptrs.emplace_back(std::move(msg2));
+  o2::framework::MessageSet msgSet([&ptrs](size_t i) -> fair::mq::MessagePtr& { return ptrs[i]; }, 2);
+
+  REQUIRE(msgSet.messages.size() == 2);
+  REQUIRE(msgSet.messageMap.size() == 1);
+  REQUIRE(msgSet.pairMap.size() == 1);
+  REQUIRE(msgSet.messageMap[0].position == 0);
+  REQUIRE(msgSet.messageMap[0].size == 1);
+
+  REQUIRE(msgSet.pairMap[0].partIndex == 0);
+  REQUIRE(msgSet.pairMap[0].payloadIndex == 0);
+}
+
+TEST_CASE("MessageSetWithMultipart") {
+  std::vector<fair::mq::MessagePtr> ptrs;
+  std::unique_ptr<fair::mq::Message> msg(nullptr);
+  std::unique_ptr<fair::mq::Message> msg2(nullptr);
+  std::unique_ptr<fair::mq::Message> msg3(nullptr);
+  ptrs.emplace_back(std::move(msg));
+  ptrs.emplace_back(std::move(msg2));
+  ptrs.emplace_back(std::move(msg3));
+  o2::framework::MessageSet msgSet([&ptrs](size_t i) -> fair::mq::MessagePtr& { return ptrs[i]; }, 3);
+
+  REQUIRE(msgSet.messages.size() == 3);
+  REQUIRE(msgSet.messageMap.size() == 1);
+  REQUIRE(msgSet.pairMap.size() == 2);
+  REQUIRE(msgSet.messageMap[0].position == 0);
+  REQUIRE(msgSet.messageMap[0].size == 2);
+
+  REQUIRE(msgSet.pairMap[0].partIndex == 0);
+  REQUIRE(msgSet.pairMap[0].payloadIndex == 0);
+  REQUIRE(msgSet.pairMap[1].partIndex == 0);
+  REQUIRE(msgSet.pairMap[1].payloadIndex == 1);
+}
+
+TEST_CASE("MessageSetAddPartRef") {
+  std::vector<fair::mq::MessagePtr> ptrs;
+  std::unique_ptr<fair::mq::Message> msg(nullptr);
+  std::unique_ptr<fair::mq::Message> msg2(nullptr);
+  ptrs.emplace_back(std::move(msg));
+  ptrs.emplace_back(std::move(msg2));
+  PartRef ref {std::move(msg), std::move(msg2)};
+  o2::framework::MessageSet msgSet;
+  msgSet.add(std::move(ref));
+
+  REQUIRE(msgSet.messages.size() == 2);
+  REQUIRE(msgSet.messageMap.size() == 1);
+  REQUIRE(msgSet.pairMap.size() == 1);
+  REQUIRE(msgSet.messageMap[0].position == 0);
+  REQUIRE(msgSet.messageMap[0].size == 1);
+
+  REQUIRE(msgSet.pairMap[0].partIndex == 0);
+  REQUIRE(msgSet.pairMap[0].payloadIndex == 0);
+}