diff --git a/src/native/corehost/fxr/command_line.cpp b/src/native/corehost/fxr/command_line.cpp
index b23f6f4bb1677d..7d82df132fc7b8 100644
--- a/src/native/corehost/fxr/command_line.cpp
+++ b/src/native/corehost/fxr/command_line.cpp
@@ -44,7 +44,7 @@ namespace
         std::vector<known_options> known_opts;
         known_opts.reserve(static_cast<int>(known_options::__last));
         known_opts.push_back(known_options::additional_probing_path);
-        if (for_cli_usage || exec_mode || mode == host_mode_t::split_fx || mode == host_mode_t::apphost)
+        if (for_cli_usage || exec_mode || mode == host_mode_t::apphost)
         {
             known_opts.push_back(known_options::deps_file);
             known_opts.push_back(known_options::runtime_config);
@@ -229,13 +229,7 @@ int command_line::parse_args_for_mode(
 {
     int argoff = args_include_running_executable ? 1 : 0;
     int result;
-    if (mode == host_mode_t::split_fx)
-    {
-        // Invoked as corehost
-        trace::verbose(_X("--- Executing in split/FX mode..."));
-        result = parse_args(host_info, argoff, argc, argv, false, mode, new_argoff, app_candidate, opts);
-    }
-    else if (mode == host_mode_t::apphost)
+    if (mode == host_mode_t::apphost)
     {
         // Invoked from the application base.
         trace::verbose(_X("--- Executing in a native executable mode..."));
diff --git a/src/native/corehost/fxr/fx_muxer.cpp b/src/native/corehost/fxr/fx_muxer.cpp
index 3dbf3de3b1a646..681ba5437a6521 100644
--- a/src/native/corehost/fxr/fx_muxer.cpp
+++ b/src/native/corehost/fxr/fx_muxer.cpp
@@ -375,27 +375,8 @@ namespace
             return host_mode_t::apphost;
         }
 
-        if (coreclr_exists_in_dir(host_info.dotnet_root))
-        {
-            // Detect between standalone apphost or legacy split mode (specifying --depsfile and --runtimeconfig)
-
-            pal::string_t deps_in_dotnet_root = host_info.dotnet_root;
-            pal::string_t deps_filename = host_info.get_app_name() + _X(".deps.json");
-            append_path(&deps_in_dotnet_root, deps_filename.c_str());
-            bool deps_exists = pal::file_exists(deps_in_dotnet_root);
-
-            trace::info(_X("Detecting mode... CoreCLR present in dotnet root [%s] and checking if [%s] file present=[%d]"),
-                host_info.dotnet_root.c_str(), deps_filename.c_str(), deps_exists);
-
-            // Name of runtimeconfig file; since no path is included here the check is in the current working directory
-            pal::string_t config_in_cwd = host_info.get_app_name() + _X(".runtimeconfig.json");
-
-            return (deps_exists || !pal::file_exists(config_in_cwd)) && pal::file_exists(host_info.app_path) ? host_mode_t::apphost : host_mode_t::split_fx;
-        }
-
         if (pal::file_exists(host_info.app_path))
         {
-            // Framework-dependent apphost
             return host_mode_t::apphost;
         }
 
@@ -522,19 +503,10 @@ namespace
                 pal::getenv(_X("DOTNET_ADDITIONAL_DEPS"), &additional_deps_serialized);
             }
 
-            // If invoking using FX dotnet.exe, use own directory.
-            if (mode == host_mode_t::split_fx)
-            {
-                auto fx = new fx_definition_t(app_config.get_frameworks()[0].get_fx_name(), host_info.dotnet_root, pal::string_t(), pal::string_t());
-                fx_definitions.push_back(std::unique_ptr<fx_definition_t>(fx));
-            }
-            else
+            rc = fx_resolver_t::resolve_frameworks_for_app(host_info.dotnet_root, override_settings, app_config, fx_definitions, mode == host_mode_t::muxer ? app_candidate.c_str() : host_info.host_path.c_str());
+            if (rc != StatusCode::Success)
             {
-                rc = fx_resolver_t::resolve_frameworks_for_app(host_info.dotnet_root, override_settings, app_config, fx_definitions, mode == host_mode_t::muxer ? app_candidate.c_str() : host_info.host_path.c_str());
-                if (rc != StatusCode::Success)
-                {
-                    return rc;
-                }
+                return rc;
             }
         }
 
diff --git a/src/native/corehost/host_interface.h b/src/native/corehost/host_interface.h
index f82d22dfceffed..250217dac12c11 100644
--- a/src/native/corehost/host_interface.h
+++ b/src/native/corehost/host_interface.h
@@ -16,11 +16,9 @@ enum host_mode_t
 
     apphost,        // Invoked as <appname>.exe from the application base; this is the renamed "apphost.exe".
 
-    split_fx,       // Invoked as "corehost.exe" for xunit scenarios. Supported for backwards compat for 1.x apps.
-                    // Split FX means, the host is operating like "corerun.exe" in a split location from the application base (CORE_ROOT equivalent),
-                    // but it has its "hostfxr.dll" next to it.
+    // split_fx = 3, // Formerly used for split-framework mode for 1.x apps.
 
-    libhost,        // Invoked from a non-exe scenario (e.g. COM Activation or self-hosting native application)
+    libhost = 4,    // Invoked from a non-exe scenario (e.g. COM Activation or self-hosting native application)
 };
 
 #define _HOST_INTERFACE_PACK 1
diff --git a/src/native/corehost/hostpolicy/hostpolicy.cpp b/src/native/corehost/hostpolicy/hostpolicy.cpp
index 165cc092f621b7..9d4761803b97a4 100644
--- a/src/native/corehost/hostpolicy/hostpolicy.cpp
+++ b/src/native/corehost/hostpolicy/hostpolicy.cpp
@@ -350,9 +350,6 @@ void trace_corehost_init(
             case host_mode_t::apphost:
                 host_mode_str = _X("apphost");
                 break;
-            case host_mode_t::split_fx:
-                host_mode_str = _X("split_fx");
-                break;
             case host_mode_t::libhost:
                 host_mode_str = _X("libhost");
                 break;