diff --git a/lib/report.js b/lib/report.js
index ac5bdb5e..53145fbb 100644
--- a/lib/report.js
+++ b/lib/report.js
@@ -119,8 +119,8 @@ class Report {
   _normalizeProcessCov (v8ProcessCov) {
     const result = []
     for (const v8ScriptCov of v8ProcessCov.result) {
-      if (/^file:[\\/]{2}/.test(v8ScriptCov.url)) {
-        v8ScriptCov.url = v8ScriptCov.url.replace(/^file:[\\/]{2}/, '')
+      if (/^file:[/]{2}/.test(v8ScriptCov.url)) {
+        v8ScriptCov.url = v8ScriptCov.url.replace(/^file:[/]{2}/, '')
       }
       if (this.exclude.shouldInstrument(v8ScriptCov.url) &&
         (!this.omitRelative || isAbsolute(v8ScriptCov.url))) {