diff --git a/src/optional/python-bindings/tests/Makefile.am b/src/optional/python-bindings/tests/Makefile.am
index c8bba5e0de..e1dda3be1e 100644
--- a/src/optional/python-bindings/tests/Makefile.am
+++ b/src/optional/python-bindings/tests/Makefile.am
@@ -4,6 +4,7 @@ TESTS_ENVIRONMENT = \
   PYTHONPATH=$(PYTHONPATH):$(top_builddir)/src/optional/python-bindings \
   PYTHONPATH=$$PYTHONPATH:$(top_builddir)/src/optional/python-bindings/.libs \
   PYTHONPATH=$$PYTHONPATH:$(top_builddir)/src/test-core/ \
+  PYTHONPATH=$$PYTHONPATH:$(top_srcdir)/src/test-core/ \
   PYTHONPATH=$$PYTHONPATH:$(top_builddir)/src/test-core/.libs \
   $(top_builddir)/src/bin/overrides/gnucash-build-env $(PYTHON)
 TESTS = runTests.py