diff --git a/lib/v8-to-istanbul.js b/lib/v8-to-istanbul.js
index d6af42e9..7d23ed17 100644
--- a/lib/v8-to-istanbul.js
+++ b/lib/v8-to-istanbul.js
@@ -31,26 +31,28 @@ module.exports = class V8ToIstanbul {
     this.branches = {}
     this.functions = {}
     this.covSources = []
+    this.rawSourceMap = undefined
     this.sourceMap = undefined
     this.sourceTranspiled = undefined
   }
 
   async load () {
     const rawSource = this.sources.source || await readFile(this.path, 'utf8')
-    const rawSourceMap = this.sources.sourceMap ||
+    this.rawSourceMap = this.sources.sourceMap ||
       // if we find a source-map (either inline, or a .map file) we load
       // both the transpiled and original source, both of which are used during
       // the backflips we perform to remap absolute to relative positions.
       convertSourceMap.fromSource(rawSource) || convertSourceMap.fromMapFileSource(rawSource, dirname(this.path))
 
-    if (rawSourceMap) {
-      if (rawSourceMap.sourcemap.sources.length > 1) {
-        this.sourceMap = await new SourceMapConsumer(rawSourceMap.sourcemap)
+    if (this.rawSourceMap) {
+      if (this.rawSourceMap.sourcemap.sources.length > 1) {
+        this.sourceMap = await new SourceMapConsumer(this.rawSourceMap.sourcemap)
         this.covSources = this.sourceMap.sourcesContent.map((rawSource, i) => ({ source: new CovSource(rawSource, this.wrapperLength), path: this.sourceMap.sources[i] }))
         this.sourceTranspiled = new CovSource(rawSource, this.wrapperLength)
       } else {
-        this._rewritePath(rawSourceMap)
-        this.sourceMap = await new SourceMapConsumer(rawSourceMap.sourcemap)
+        const candidatePath = this.rawSourceMap.sourcemap.sources.length >= 1 ? this.rawSourceMap.sourcemap.sources[0] : this.rawSourceMap.sourcemap.file
+        this.path = this._resolveSource(this.rawSourceMap, candidatePath)
+        this.sourceMap = await new SourceMapConsumer(this.rawSourceMap.sourcemap)
 
         let originalRawSource
         // If the source map has inline source content then it should be here
@@ -64,8 +66,7 @@ module.exports = class V8ToIstanbul {
         } else {
           originalRawSource = await readFile(this.path, 'utf8')
         }
-
-        this.covSources = [{ source: new CovSource(originalRawSource, this.wrapperLength), path: this.sourceMap.sources[0] }]
+        this.covSources = [{ source: new CovSource(originalRawSource, this.wrapperLength), path: this.path }]
         this.sourceTranspiled = new CovSource(rawSource, this.wrapperLength)
       }
     } else {
@@ -73,15 +74,15 @@ module.exports = class V8ToIstanbul {
     }
   }
 
-  _rewritePath (rawSourceMap) {
+  _resolveSource (rawSourceMap, sourcePath) {
+    sourcePath = sourcePath.replace(/(^file:\/\/)|(^webpack:\/\/)/, '')
     const sourceRoot = rawSourceMap.sourcemap.sourceRoot ? rawSourceMap.sourcemap.sourceRoot.replace('file://', '') : ''
-    const sourcePath = rawSourceMap.sourcemap.sources.length >= 1 ? rawSourceMap.sourcemap.sources[0].replace('file://', '') : rawSourceMap.sourcemap.file
     const candidatePath = join(sourceRoot, sourcePath)
 
     if (isAbsolute(candidatePath)) {
-      this.path = candidatePath
+      return candidatePath
     } else {
-      this.path = resolve(dirname(this.path), candidatePath)
+      return resolve(dirname(this.path), candidatePath)
     }
   }
 
@@ -181,7 +182,7 @@ module.exports = class V8ToIstanbul {
 
       const matchingSource = this.covSources.find(covSource => covSource.path === source)
       covSource = matchingSource ? matchingSource.source : this.covSources[0].source
-      path = matchingSource ? matchingSource.path : this.covSources[0].path;
+      path = matchingSource ? matchingSource.path : this.covSources[0].path
 
       // next we convert these relative positions back to absolute positions
       // in the original source (which is the format expected in the next step).
@@ -198,13 +199,24 @@ module.exports = class V8ToIstanbul {
   }
 
   getInnerIstanbul (source, path) {
-    if (this.excludePath(path)) {
+    // We apply the "Resolving Sources" logic (as defined in
+    // sourcemaps.info/spec.html) as a final step for 1:many source maps.
+    // for 1:1 source maps, the resolve logic is applied while loading.
+    //
+    // TODO: could we move the resolving logic for 1:1 source maps to the final
+    // step as well? currently this breaks some tests in c8.
+    let resolvedPath = path
+    if (this.rawSourceMap && this.rawSourceMap.sourcemap.sources.length > 1) {
+      resolvedPath = this._resolveSource(this.rawSourceMap, path)
+    }
+
+    if (this.excludePath(resolvedPath)) {
       return
     }
 
     return {
-      [path]: {
-        path,
+      [resolvedPath]: {
+        path: resolvedPath,
         ...this._statementsToIstanbul(source, path),
         ...this._branchesToIstanbul(source, path),
         ...this._functionsToIstanbul(source, path)
diff --git a/tap-snapshots/test-v8-to-istanbul.js-TAP.test.js b/tap-snapshots/test-v8-to-istanbul.js-TAP.test.js
index 71b50fcb..51c0399e 100644
--- a/tap-snapshots/test-v8-to-istanbul.js-TAP.test.js
+++ b/tap-snapshots/test-v8-to-istanbul.js-TAP.test.js
@@ -5,7 +5,7 @@
  * Make sure to inspect the output below.  Do not ignore changes!
  */
 'use strict'
-exports[`test/v8-to-istanbul.js TAP > must match branches snapshot 1`] = `
+exports['test/v8-to-istanbul.js TAP > must match branches snapshot 1'] = `
 Object {
   "b": Object {
     "0": Array [
@@ -620,7 +620,7 @@ Object {
 }
 `
 
-exports[`test/v8-to-istanbul.js TAP > must match functions snapshot 1`] = `
+exports['test/v8-to-istanbul.js TAP > must match functions snapshot 1'] = `
 Object {
   "b": Object {
     "0": Array [
@@ -1601,7 +1601,7 @@ Object {
 }
 `
 
-exports[`test/v8-to-istanbul.js TAP > must match mixed new lines snapshot 1`] = `
+exports['test/v8-to-istanbul.js TAP > must match mixed new lines snapshot 1'] = `
 Object {
   "b": Object {
     "0": Array [
@@ -1707,7 +1707,7 @@ Object {
 }
 `
 
-exports[`test/v8-to-istanbul.js TAP > must match shebang snapshot 1`] = `
+exports['test/v8-to-istanbul.js TAP > must match shebang snapshot 1'] = `
 Object {
   "b": Object {
     "0": Array [
@@ -1868,7 +1868,7 @@ Object {
 }
 `
 
-exports[`test/v8-to-istanbul.js TAP > must match source-map and minified source snapshot 1`] = `
+exports['test/v8-to-istanbul.js TAP > must match source-map and minified source snapshot 1'] = `
 Object {
   "b": Object {
     "0": Array [
@@ -2570,7 +2570,7 @@ Object {
 }
 `
 
-exports[`test/v8-to-istanbul.js TAP > must match source-map with multiple source files snapshot 1`] = `
+exports['test/v8-to-istanbul.js TAP > must match source-map with multiple source files snapshot 1'] = `
 Object {
   "b": Object {},
   "branchMap": Object {},
diff --git a/test/v8-to-istanbul.js b/test/v8-to-istanbul.js
index dbda9c4a..6765966d 100644
--- a/test/v8-to-istanbul.js
+++ b/test/v8-to-istanbul.js
@@ -137,7 +137,7 @@ ${'//'}${'#'} sourceMappingURL=data:application/json;base64,${base64Sourcemap}
           endOffset: 1
         }]
       }])
-      Object.keys(v8ToIstanbul.toIstanbul()).should.eql(['webpack:///src/index.ts', 'webpack:///src/utils.ts'])
+      Object.keys(v8ToIstanbul.toIstanbul()).should.eql(['/src/index.ts', '/src/utils.ts'])
     })
   })
 
@@ -175,7 +175,7 @@ ${'//'}${'#'} sourceMappingURL=data:application/json;base64,${base64Sourcemap}
       await v8ToIstanbul.load()
 
       v8ToIstanbul.covSources.length.should.equal(3)
-      Object.keys(v8ToIstanbul.toIstanbul()).should.eql(['webpack:///webpack/bootstrap', 'webpack:///src/index.ts', 'webpack:///src/utils.ts'])
+      Object.keys(v8ToIstanbul.toIstanbul()).should.eql(['/webpack/bootstrap', '/src/index.ts', '/src/utils.ts'])
     })
   })