diff --git a/coverage/xmlreport.py b/coverage/xmlreport.py
index 2c8fd0cc1..b2180266d 100644
--- a/coverage/xmlreport.py
+++ b/coverage/xmlreport.py
@@ -69,6 +69,8 @@ def __init__(self, coverage: Coverage) -> None:
                 if os.path.exists(src):
                     if not self.config.relative_files:
                         src = files.canonical_filename(src)
+                    else:
+                        src = src.rstrip(r"\/")
                     self.source_paths.add(src)
         self.packages: Dict[str, PackageData] = {}
         self.xml_out: xml.dom.minidom.Document
diff --git a/tests/test_xml.py b/tests/test_xml.py
index 94b310e3e..0f2cff419 100644
--- a/tests/test_xml.py
+++ b/tests/test_xml.py
@@ -320,7 +320,7 @@ def test_accented_directory(self) -> None:
 
     def test_no_duplicate_packages(self) -> None:
         self.make_file(
-            "namespace/package/__init__.py", 
+            "namespace/package/__init__.py",
             "from . import sample; from . import test; from .subpackage import test"
         )
         self.make_file("namespace/package/sample.py", "print('package.sample')")
@@ -489,6 +489,19 @@ def test_relative_source(self) -> None:
         elts = dom.findall(".//sources/source")
         assert [elt.text for elt in elts] == ["src"]
 
+    def test_relative_source_trailing_slash(self) -> None:
+        self.make_file("src/mod.py", "print(17)")
+        cov = coverage.Coverage(source=["src/"])
+        cov.set_option("run:relative_files", True)
+        self.start_import_stop(cov, "mod", modfile="src/mod.py")
+        cov.xml_report()
+
+        with open("coverage.xml") as x:
+            print(x.read())
+        dom = ElementTree.parse("coverage.xml")
+        elts = dom.findall(".//sources/source")
+        assert [elt.text for elt in elts] == ["src"]
+
 
 def compare_xml(expected: str, actual: str, actual_extra: bool = False) -> None:
     """Specialized compare function for our XML files."""