diff --git a/tests/testthat/setup.R b/tests/testthat/setup.R
new file mode 100644
index 00000000..0fb3b41f
--- /dev/null
+++ b/tests/testthat/setup.R
@@ -0,0 +1,4 @@
+# Quiet bgms's advisory verbose output (warmup-length warnings, data-cleaning
+# messages) during the test run. Tests that specifically assert this output set
+# options(bgms.verbose = TRUE) locally, which overrides this default.
+options(bgms.verbose = FALSE)