diff --git a/Lib/test/regrtest.py b/Lib/test/regrtest.py
index 8e9fe65..59f57d5 100755
--- a/Lib/test/regrtest.py
+++ b/Lib/test/regrtest.py
@@ -22,7 +22,8 @@
 -h/--help       -- print this text and exit
 --timeout TIMEOUT
                 -- dump the traceback and exit if a test takes more
-                   than TIMEOUT seconds
+                   than TIMEOUT seconds (default: 15 minutes); disable
+                   the timeout if TIMEOUT is zero
 
 Verbosity
 
@@ -239,7 +240,7 @@
          findleaks=False, use_resources=None, trace=False, coverdir='coverage',
          runleaks=False, huntrleaks=False, verbose2=False, print_slow=False,
          random_seed=None, use_mp=None, verbose3=False, forever=False,
-         header=False, timeout=None):
+         header=False, timeout=15*60):
     """Execute a test suite.
 
     This also parses command-line options and modifies its behavior
diff --git a/Misc/NEWS b/Misc/NEWS
index 985e359..5a0e8a3 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -361,7 +361,9 @@
 Tests
 -----
 
-- Issue #11727: add --timeout option to regrtest (disabled by default).
+- Issue #11727: If a test takes more than 15 minutes, regrtest dumps the
+  traceback of all threads and exits. Use --timeout option to change the
+  default timeout or to disable it.
 
 - Issue #11653: fix -W with -j in regrtest.