diff --git a/src/reporter.js b/src/reporter.js
index 0075f79..f537cfc 100644
--- a/src/reporter.js
+++ b/src/reporter.js
@@ -102,8 +102,13 @@ function CoverageIstanbulReporter(baseReporterDecorator, logger, config) {
       .map;
 
     if (!coverageConfig.skipFilesWithNoCoverage) {
+      // On Windows, istanbul returns files with mixed forward/backslashes in them
+      const fixedFilePaths = {};
+      remappedCoverageMap.files().forEach(path => {
+        fixedFilePaths[util.fixPathSeparators(path)] = true;
+      });
       coverageMap.files().forEach(path => {
-        if (!(path in remappedCoverageMap)) {
+        if (!(util.fixPathSeparators(path) in fixedFilePaths)) {
           // Re-add empty coverage record
           remappedCoverageMap.addFileCoverage(path);
         }
diff --git a/src/util.js b/src/util.js
index 76b85a4..b54309b 100644
--- a/src/util.js
+++ b/src/util.js
@@ -90,6 +90,7 @@ function overrideThresholds(key, overrides, basePath) {
   return thresholds;
 }
 
+module.exports.fixPathSeparators = fixPathSeparators;
 module.exports.fixWebpackSourcePaths = fixWebpackSourcePaths;
 module.exports.fixWebpackFilePath = fixWebpackFilePath;
 module.exports.overrideThresholds = overrideThresholds;