diff --git a/Trigger/TrigT1/Muon/L0MuonS1RPC/CMakeLists.txt b/Trigger/TrigT1/Muon/L0MuonS1RPC/CMakeLists.txt
new file mode 100644
index 0000000000000000000000000000000000000000..07aed5bff4fec873566cb75bfc0a37767f006231
--- /dev/null
+++ b/Trigger/TrigT1/Muon/L0MuonS1RPC/CMakeLists.txt
@@ -0,0 +1,17 @@
+# Copyright (C) 2002-2025 CERN for the benefit of the ATLAS collaboration
+
+atlas_subdir ( L0MuonS1RPC )
+
+find_package( CLHEP )
+
+atlas_add_component (L0MuonS1RPC
+ src/*.cxx src/components/*.cxx
+ INCLUDE_DIRS ${CLHEP_INCLUDE_DIRS}
+ LINK_LIBRARIES AnaAlgorithmLib AthenaKernel xAODMuonRDO MuonDigitContainer xAODTrigger AthenaMonitoringKernelLib
+ MuonCablingData xAODTrigger
+ PRIVATE_LINK_LIBRARIES ${CLHEP_LIBRARIES} )
+
+
+atlas_install_python_modules( python/*.py POST_BUILD_CMD ${ATLAS_FLAKE8} --extend-extensions=ATL901 )
+
+
diff --git a/Trigger/TrigT1/Muon/L0MuonS1RPC/python/L0MuonS1RPCConfig.py b/Trigger/TrigT1/Muon/L0MuonS1RPC/python/L0MuonS1RPCConfig.py
new file mode 100644
index 0000000000000000000000000000000000000000..0a174df88a694ad12a497fb7c90411dbd4f53ad3
--- /dev/null
+++ b/Trigger/TrigT1/Muon/L0MuonS1RPC/python/L0MuonS1RPCConfig.py
@@ -0,0 +1,62 @@
+#Copyright (C) 2002-2025 CERN for the benefit of the ATLAS collaboration
+from AthenaConfiguration.ComponentFactory import CompFactory
+from AthenaConfiguration.ComponentAccumulator import ComponentAccumulator
+
+from AthenaCommon.Logging import logging
+_log = logging.getLogger(__name__)
+
+def L0MuonRPCSimCfg(flags, name = "L0MuonRPCSim", **kwargs):
+
+ result = ComponentAccumulator()
+
+ alg = CompFactory.L0Muon.L0MuonRPCSim(name = name,
+ **kwargs)
+
+ from AthenaMonitoringKernel.GenericMonitoringTool import GenericMonitoringTool
+ monTool = GenericMonitoringTool(flags, 'MonTool')
+ monTool.HistPath = 'L0MuonRPCSim'
+ monTool.defineHistogram('track_input_eta', path='EXPERT', type='TH1F', title=';#eta_{#mu}^{truth};Muons', xbins=50, xmin=-3, xmax=3)
+
+ alg.MonTool = monTool
+
+ histSvc = CompFactory.THistSvc(Output=["EXPERT DATAFILE='" + name + ".root' OPT='RECREATE'"])
+
+ result.addEventAlgo(alg)
+ result.addService(histSvc)
+ return result
+
+
+if __name__ == "__main__":
+
+ from AthenaConfiguration.TestDefaults import defaultTestFiles
+ from AthenaConfiguration.AllConfigFlags import initConfigFlags
+ from AthenaCommon.Constants import DEBUG
+ flags = initConfigFlags()
+ flags.Input.Files = defaultTestFiles.AOD_RUN3_MC
+ flags.Exec.MaxEvents = 20
+ flags.Common.MsgSuppression = False
+ flags.lock()
+
+ # create basic infrastructure
+ from AthenaConfiguration.MainServicesConfig import MainServicesCfg
+ acc = MainServicesCfg(flags)
+
+ from AthenaPoolCnvSvc.PoolReadConfig import PoolReadCfg
+ acc.merge(PoolReadCfg(flags))
+
+ # example simulation alg
+ simAlg = L0MuonRPCSimCfg(flags,
+ name = "L0MuonRPCSim",
+ OutputLevel = DEBUG)
+ acc.merge(simAlg)
+
+ # below is validation
+ acc.printConfig(withDetails=True, summariseProps=True)
+
+ # run the job
+ status = acc.run()
+
+ # report the execution status (0 ok, else error)
+ import sys
+ sys.exit(not status.isSuccess())
+
diff --git a/Trigger/TrigT1/Muon/L0MuonS1RPC/src/L0MuonRPCSim.cxx b/Trigger/TrigT1/Muon/L0MuonS1RPC/src/L0MuonRPCSim.cxx
new file mode 100644
index 0000000000000000000000000000000000000000..09558c8c4327f48e163d1ab5c2f52bdaf383695c
--- /dev/null
+++ b/Trigger/TrigT1/Muon/L0MuonS1RPC/src/L0MuonRPCSim.cxx
@@ -0,0 +1,76 @@
+/*
+ Copyright (C) 2002-2025 CERN for the benefit of the ATLAS collaboration
+*/
+
+#include "L0MuonRPCSim.h"
+
+#include "xAODTrigger/MuonRoIAuxContainer.h"
+
+namespace L0Muon {
+
+L0MuonRPCSim::L0MuonRPCSim(const std::string& name, ISvcLocator* pSvcLocator)
+: AthReentrantAlgorithm(name, pSvcLocator) {}
+
+
+L0MuonRPCSim::~L0MuonRPCSim() {}
+
+
+StatusCode L0MuonRPCSim::initialize() {
+ ATH_MSG_INFO("Initializing " << name() << "...");
+
+ ATH_CHECK(m_keyRpcRdo.initialize());
+ ATH_CHECK(m_keyRpcDigit.initialize());
+ ATH_CHECK(m_cablingKey.initialize());
+
+ /// container of output RoIs
+ ATH_CHECK(m_outputMuonRoIKey.initialize());
+
+ /// retrieve the monitoring tool
+ if (!m_monTool.empty()) ATH_CHECK(m_monTool.retrieve());
+
+ return StatusCode::SUCCESS;
+}
+
+
+StatusCode L0MuonRPCSim::finalize() {
+ ATH_MSG_INFO ("Finalizing " << name() << "...");
+ return StatusCode::SUCCESS;
+}
+
+
+StatusCode L0MuonRPCSim::execute(const EventContext& ctx) const {
+ ATH_MSG_DEBUG ("Executing " << name() << "...");
+
+ SG::ReadHandle<xAOD::NRPCRDOContainer> rpcRdo_handle(m_keyRpcRdo,ctx);
+ const xAOD::NRPCRDOContainer* inputRDO = rpcRdo_handle.cptr();
+ if ( not inputRDO ) {
+ ATH_MSG_FATAL("Unable to retrieve input RPC RDO container: " << m_keyRpcRdo.key());
+ return StatusCode::FAILURE;
+ }
+ ATH_MSG_DEBUG("Number of RPC RDO: " << inputRDO->size());
+
+ SG::ReadCondHandle cablingMap{m_cablingKey, ctx};
+ ATH_CHECK(cablingMap.isValid());
+
+ /// monitor RDO quantities
+ if ( !m_monTool.empty() ) {
+
+ auto n_of_RDO = Monitored::Scalar<unsigned int>("n_of_RDO",inputRDO->size());
+
+ }
+
+
+ /// output RoIs container
+ SG::WriteHandle<xAOD::MuonRoIContainer> outputRoI_handle(m_outputMuonRoIKey, ctx);
+ ATH_CHECK(outputRoI_handle.record(std::make_unique<xAOD::MuonRoIContainer>(), std::make_unique<xAOD::MuonRoIAuxContainer>()));
+ auto outputRoIs = outputRoI_handle.ptr();
+
+ /// Create an RoI
+ outputRoIs->push_back(std::make_unique<xAOD::MuonRoI>());
+
+
+ return StatusCode::SUCCESS;
+}
+
+
+} // end of namespace
diff --git a/Trigger/TrigT1/Muon/L0MuonS1RPC/src/L0MuonRPCSim.h b/Trigger/TrigT1/Muon/L0MuonS1RPC/src/L0MuonRPCSim.h
new file mode 100644
index 0000000000000000000000000000000000000000..7df9c4ef2792b6c784b5501278c3225fcd080d2c
--- /dev/null
+++ b/Trigger/TrigT1/Muon/L0MuonS1RPC/src/L0MuonRPCSim.h
@@ -0,0 +1,49 @@
+/*
+ Copyright (C) 2002-2025 CERN for the benefit of the ATLAS collaboration
+*/
+#ifndef L0MUONRPCSIM_H
+#define L0MUONRPCSIM_H
+
+#include "AthenaBaseComps/AthReentrantAlgorithm.h"
+#include "AthenaMonitoringKernel/Monitored.h"
+#include "AthenaKernel/IAthRNGSvc.h"
+
+#include "StoreGate/ReadHandleKey.h"
+#include "xAODMuonRDO/NRPCRDOContainer.h"
+#include "xAODTrigger/MuonRoIContainer.h"
+#include "MuonDigitContainer/RpcDigitContainer.h"
+#include "MuonCablingData/RpcCablingMap.h"
+
+namespace L0Muon {
+
+class L0MuonRPCSim: public ::AthReentrantAlgorithm {
+ public:
+ L0MuonRPCSim(const std::string& name, ISvcLocator* pSvcLocator);
+ virtual ~L0MuonRPCSim();
+
+ virtual StatusCode initialize() override;
+ virtual StatusCode execute(const EventContext& ctx) const override;
+ virtual StatusCode finalize() override;
+
+ private:
+
+ /// RPC Digit container
+ SG::ReadHandleKey<RpcDigitContainer> m_keyRpcDigit{this,"InputDigit","RpcDigitContainer","Location of input RpcDigitContainer"};
+ /// RPC Rdo
+ SG::ReadHandleKey<xAOD::NRPCRDOContainer> m_keyRpcRdo{this,"NrpcRdoKey","NRPCRDO","Location of input RpcRDO"};
+ /// Output RoIs
+ SG::WriteHandleKey<xAOD::MuonRoIContainer> m_outputMuonRoIKey{this, "L0MuonBarrelKey", "L0MuonBarrelRoI",
+ "key for LVL0 Muon RoIs in the barrel" };
+
+
+ /// NRPC cabling map
+ SG::ReadCondHandleKey<Muon::RpcCablingMap> m_cablingKey{this, "CablingKey", "MuonNRPC_CablingMap","Key of MuonNRPC_CablingMap"};
+
+ ToolHandle<GenericMonitoringTool> m_monTool{this, "MonTool", "", "Monitoring Tool"};
+
+};
+
+} // end of namespace
+
+#endif // L0MUONRPCSIM_H
+
diff --git a/Trigger/TrigT1/Muon/L0MuonS1RPC/src/components/L0MuonS1RPC_entries.cxx b/Trigger/TrigT1/Muon/L0MuonS1RPC/src/components/L0MuonS1RPC_entries.cxx
new file mode 100644
index 0000000000000000000000000000000000000000..e8893fcd15acccd1f3d678c94f52f39cc7f77bcb
--- /dev/null
+++ b/Trigger/TrigT1/Muon/L0MuonS1RPC/src/components/L0MuonS1RPC_entries.cxx
@@ -0,0 +1,2 @@
+#include "../L0MuonRPCSim.h"
+DECLARE_COMPONENT( L0Muon::L0MuonRPCSim )