diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 1ab606e..f083add 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -97,6 +97,10 @@ jobs:
             file: .tool-versions
             run: |
               echo "bun1.1.0" > .tool-versions
+          - name: .tool-versions (bun  1.1.0)
+            file: .tool-versions
+            run: |
+              echo "bun  1.1.0" > .tool-versions
           - name: .bumrc (1.1.0)
             file: .bumrc
             run: |
diff --git a/src/utils.ts b/src/utils.ts
index aea7160..a8b69c0 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -31,7 +31,7 @@ const FILE_VERSION_READERS = {
   "package.json": (content: string) =>
     JSON.parse(content).packageManager?.split("bun@")?.[1],
   ".tool-versions": (content: string) =>
-    content.match(/^bun\s?(?<version>.*?)$/m)?.groups?.version,
+    content.match(/^bun\s*(?<version>.*?)$/m)?.groups?.version,
   ".bumrc": (content: string) => content, // https://github.com/owenizedd/bum
   ".bun-version": (content: string) => content,
 };