diff --git a/freqtrade/data/btanalysis.py b/freqtrade/data/btanalysis.py
index c5905acde..63a75e0af 100644
--- a/freqtrade/data/btanalysis.py
+++ b/freqtrade/data/btanalysis.py
@@ -184,7 +184,7 @@ def get_backtest_resultlist(dirname: Path):
             continue
         for s, v in metadata.items():
             results.append({
-                'filename': filename.name,
+                'filename': filename.stem,
                 'strategy': s,
                 'run_id': v['run_id'],
                 'backtest_start_time': v['backtest_start_time'],
diff --git a/freqtrade/rpc/api_server/api_backtest.py b/freqtrade/rpc/api_server/api_backtest.py
index 3fac83e1e..f3222a97b 100644
--- a/freqtrade/rpc/api_server/api_backtest.py
+++ b/freqtrade/rpc/api_server/api_backtest.py
@@ -247,7 +247,8 @@ def api_backtest_history(config=Depends(get_config)):
 def api_backtest_history_result(filename: str, strategy: str, config=Depends(get_config)):
     # Get backtest result history, read from metadata files
     bt_results_base: Path = config['user_data_dir'] / 'backtest_results'
-    fn = bt_results_base / filename
+    fn = (bt_results_base / filename).with_suffix('.json')
+
     results: Dict[str, Any] = {
         'metadata': {},
         'strategy': {},
@@ -271,7 +272,7 @@ def api_backtest_history_result(filename: str, strategy: str, config=Depends(get
 def api_delete_backtest_history_entry(file: str, config=Depends(get_config)):
     # Get backtest result history, read from metadata files
     bt_results_base: Path = config['user_data_dir'] / 'backtest_results'
-    file_abs = bt_results_base / file
+    file_abs = (bt_results_base / file).with_suffix('.json')
     # Ensure file is in backtest_results directory
     if not is_file_in_dir(file_abs, bt_results_base):
         raise HTTPException(status_code=404, detail="File not found.")
diff --git a/tests/rpc/test_rpc_apiserver.py b/tests/rpc/test_rpc_apiserver.py
index c37553f24..fa5492442 100644
--- a/tests/rpc/test_rpc_apiserver.py
+++ b/tests/rpc/test_rpc_apiserver.py
@@ -2000,7 +2000,7 @@ def test_api_backtest_history(botclient, mocker, testdatadir):
     result = rc.json()
     assert len(result) == 3
     fn = result[0]['filename']
-    assert fn == "backtest-result_multistrat.json"
+    assert fn == "backtest-result_multistrat"
     strategy = result[0]['strategy']
     rc = client_get(client, f"{BASE_URI}/backtest/history/result?filename={fn}&strategy={strategy}")
     assert_response(rc)