diff --git a/tests/strategy/test_interface.py b/tests/strategy/test_interface.py
index 713ffa5cb..204fa996d 100644
--- a/tests/strategy/test_interface.py
+++ b/tests/strategy/test_interface.py
@@ -9,6 +9,7 @@ import pytest
 from pandas import DataFrame
 
 from freqtrade.configuration import TimeRange
+from freqtrade.constants import CUSTOM_TAG_MAX_LENGTH
 from freqtrade.data.dataprovider import DataProvider
 from freqtrade.data.history import load_data
 from freqtrade.enums import ExitCheckTuple, ExitType, HyperoptState, SignalDirection
@@ -529,13 +530,13 @@ def test_custom_exit(default_conf, fee, caplog) -> None:
     assert res[0].exit_reason == 'hello world'
 
     caplog.clear()
-    strategy.custom_exit = MagicMock(return_value='h' * 100)
+    strategy.custom_exit = MagicMock(return_value='h' * CUSTOM_TAG_MAX_LENGTH * 2)
     res = strategy.should_exit(trade, 1, now,
                                enter=False, exit_=False,
                                low=None, high=None)
     assert res[0].exit_type == ExitType.CUSTOM_EXIT
     assert res[0].exit_flag is True
-    assert res[0].exit_reason == 'h' * 64
+    assert res[0].exit_reason == 'h' * (CUSTOM_TAG_MAX_LENGTH)
     assert log_has_re('Custom exit reason returned from custom_exit is too long.*', caplog)