diff --git a/src/sage/env.py b/src/sage/env.py
index a6a99ca9303..bb228e7f041 100644
--- a/src/sage/env.py
+++ b/src/sage/env.py
@@ -220,7 +220,7 @@ def var(key: str, *fallbacks: Optional[str], force: bool = False) -> Optional[st
 MAXIMA_FAS = var("MAXIMA_FAS")
 KENZO_FAS = var("KENZO_FAS")
 SAGE_NAUTY_BINS_PREFIX = var("SAGE_NAUTY_BINS_PREFIX", "")
-SAGE_ECMBIN = var("SAGE_ECMBIN")
+SAGE_ECMBIN = var("SAGE_ECMBIN", "ecm")
 RUBIKS_BINS_PREFIX = var("RUBIKS_BINS_PREFIX", "")
 FOURTITWO_HILBERT = var("FOURTITWO_HILBERT")
 FOURTITWO_MARKOV = var("FOURTITWO_MARKOV")