diff --git a/.travis.yml b/.travis.yml
index 34ffcfe1a..2f636f223 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -33,6 +33,7 @@ script:
   - python Tests/run.py --coverage
 
 after_success:
+  - coverage combine
   - coverage report
   - coveralls
   - pip install pep8 pyflakes
diff --git a/Tests/tester.py b/Tests/tester.py
index 058e8305b..690acbafb 100644
--- a/Tests/tester.py
+++ b/Tests/tester.py
@@ -303,7 +303,7 @@ def _setup():
     import sys
     if "--coverage" in sys.argv:
         import coverage
-        cov = coverage.coverage(auto_data=True, include="PIL/*")
+        cov = coverage.coverage(auto_data=True, data_suffix=True, include="PIL/*")
         cov.start()
 
     def report():