diff --git a/src/compiler/emitter.ts b/src/compiler/emitter.ts
index 83c54f4001e..cbc78cb9bf8 100644
--- a/src/compiler/emitter.ts
+++ b/src/compiler/emitter.ts
@@ -1,6 +1,6 @@
 namespace ts {
     /*@internal*/
-    export const infoExtension = ".tsbundleinfo";
+    export const infoFile = ".tsbuildinfo";
     const brackets = createBracketsMap();
     const syntheticParent: TextRange = { pos: -1, end: -1 };
 
@@ -46,7 +46,7 @@ namespace ts {
         const sourceMapFilePath = jsFilePath && getSourceMapFilePath(jsFilePath, options);
         const declarationFilePath = (forceDtsPaths || getEmitDeclarations(options)) ? removeFileExtension(outPath) + Extension.Dts : undefined;
         const declarationMapPath = declarationFilePath && getAreDeclarationMapsEnabled(options) ? declarationFilePath + ".map" : undefined;
-        const bundleInfoPath = options.composite && jsFilePath ? (removeFileExtension(jsFilePath) + infoExtension) : undefined;
+        const bundleInfoPath = options.composite && jsFilePath ? combinePaths(getDirectoryPath(jsFilePath), infoFile) : undefined;
         return { jsFilePath, sourceMapFilePath, declarationFilePath, declarationMapPath, bundleInfoPath };
     }
 
diff --git a/src/testRunner/unittests/tsbuild.ts b/src/testRunner/unittests/tsbuild.ts
index c2eb6d5aff0..c342aacf196 100644
--- a/src/testRunner/unittests/tsbuild.ts
+++ b/src/testRunner/unittests/tsbuild.ts
@@ -506,7 +506,7 @@ export const b = new A();`);
                         if (path.startsWith("/src/")) {
                             actualReadFileMap.set(path, (actualReadFileMap.get(path) || 0) + 1);
                         }
-                        if (withoutBundleInfo && fileExtensionIs(path, infoExtension)) {
+                        if (withoutBundleInfo && getBaseFileName(path) === infoFile) {
                             return undefined;
                         }
                         return originalReadFile.call(host, path);
@@ -514,7 +514,7 @@ export const b = new A();`);
                     if (withoutBundleInfo) {
                         const originalWriteFile = host.writeFile;
                         host.writeFile = (fileName, content, writeByteOrder) => {
-                            return !fileExtensionIs(fileName, infoExtension) &&
+                            return getBaseFileName(fileName) !== infoFile &&
                                 originalWriteFile.call(host, fileName, content, writeByteOrder);
                         };
                     }