diff --git a/src/init.cpp b/src/init.cpp
index fae45eb90a5..fc6981c3ee4 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -630,7 +630,7 @@ void SetupServerArgs(ArgsManager& argsman, bool can_listen_ipc)
 
     SetupChainParamsBaseOptions(argsman);
 
-    argsman.AddArg("-acceptnonstdtxn", strprintf("Relay and mine \"non-standard\" transactions (test networks only; default: %u)", DEFAULT_ACCEPT_NON_STD_TXN), ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::NODE_RELAY);
+    argsman.AddArg("-acceptnonstdtxn", strprintf("Relay and mine \"non-standard\" transactions (test networks only; default: %u, testnet4: %u)", DEFAULT_ACCEPT_NON_STD_TXN, false), ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::NODE_RELAY);
     argsman.AddArg("-incrementalrelayfee=<amt>", strprintf("Fee rate (in %s/kvB) used to define cost of relay, used for mempool limiting and replacement policy. (default: %s)", CURRENCY_UNIT, FormatMoney(DEFAULT_INCREMENTAL_RELAY_FEE)), ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::NODE_RELAY);
     argsman.AddArg("-dustrelayfee=<amt>", strprintf("Fee rate (in %s/kvB) used to define dust, the value of an output such that it will cost more than its value in fees at this fee rate to spend it. (default: %s)", CURRENCY_UNIT, FormatMoney(DUST_RELAY_TX_FEE)), ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::NODE_RELAY);
     argsman.AddArg("-acceptstalefeeestimates", strprintf("Read fee estimates even if they are stale (%sdefault: %u) fee estimates are considered stale if they are %s hours old", "regtest only; ", DEFAULT_ACCEPT_STALE_FEE_ESTIMATES, Ticks<std::chrono::hours>(MAX_FILE_AGE)), ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::DEBUG_TEST);
diff --git a/src/node/mempool_args.cpp b/src/node/mempool_args.cpp
index e3bf5fb57cb..98aedfc3f80 100644
--- a/src/node/mempool_args.cpp
+++ b/src/node/mempool_args.cpp
@@ -87,8 +87,7 @@ util::Result<void> ApplyArgsManOptions(const ArgsManager& argsman, const CChainP
         mempool_opts.max_datacarrier_bytes = std::nullopt;
     }
 
-    mempool_opts.require_standard = !argsman.GetBoolArg("-acceptnonstdtxn", DEFAULT_ACCEPT_NON_STD_TXN);
-    if (!chainparams.IsTestChain() && !mempool_opts.require_standard) {
+    mempool_opts.require_standard = !argsman.GetBoolArg("-acceptnonstdtxn", chainparams.GetChainType() == ChainType::TESTNET4 ? true : DEFAULT_ACCEPT_NON_STD_TXN); if (!chainparams.IsTestChain() && !mempool_opts.require_standard) {
         return util::Error{Untranslated(strprintf("acceptnonstdtxn is not currently supported for %s chain", chainparams.GetChainTypeString()))};
     }