diff --git a/docs/config/index.md b/docs/config/index.md
index a8c596c2f135..6f768ab4cf62 100644
--- a/docs/config/index.md
+++ b/docs/config/index.md
@@ -1103,7 +1103,7 @@ List of files included in coverage as glob patterns
 #### coverage.extension
 
 - **Type:** `string | string[]`
-- **Default:** `['.js', '.cjs', '.mjs', '.ts', '.mts', '.cts', '.tsx', '.jsx', '.vue', '.svelte', '.marko']`
+- **Default:** `['.js', '.cjs', '.mjs', '.ts', '.mts', '.tsx', '.jsx', '.vue', '.svelte', '.marko']`
 - **Available for providers:** `'v8' | 'istanbul'`
 - **CLI:** `--coverage.extension=<extension>`, `--coverage.extension=<extension1> --coverage.extension=<extension2>`
 
diff --git a/docs/guide/cli-table.md b/docs/guide/cli-table.md
index c343c3bb6250..1ffef7e1f322 100644
--- a/docs/guide/cli-table.md
+++ b/docs/guide/cli-table.md
@@ -20,7 +20,7 @@
 | `--coverage.enabled` | Enables coverage collection. Can be overridden using the `--coverage` CLI option (default: `false`) |
 | `--coverage.include <pattern>` | Files included in coverage as glob patterns. May be specified more than once when using multiple patterns (default: `**`) |
 | `--coverage.exclude <pattern>` | Files to be excluded in coverage. May be specified more than once when using multiple extensions (default: Visit [`coverage.exclude`](https://vitest.dev/config/#coverage-exclude)) |
-| `--coverage.extension <extension>` | Extension to be included in coverage. May be specified more than once when using multiple extensions (default: `[".js", ".cjs", ".mjs", ".ts", ".mts", ".cts", ".tsx", ".jsx", ".vue", ".svelte"]`) |
+| `--coverage.extension <extension>` | Extension to be included in coverage. May be specified more than once when using multiple extensions (default: `[".js", ".cjs", ".mjs", ".ts", ".mts", ".tsx", ".jsx", ".vue", ".svelte"]`) |
 | `--coverage.clean` | Clean coverage results before running tests (default: true) |
 | `--coverage.cleanOnRerun` | Clean coverage report on watch rerun (default: true) |
 | `--coverage.reportsDirectory <path>` | Directory to write coverage report to (default: ./coverage) |
diff --git a/packages/vitest/src/defaults.ts b/packages/vitest/src/defaults.ts
index 4b1ade73230b..cd412103235e 100644
--- a/packages/vitest/src/defaults.ts
+++ b/packages/vitest/src/defaults.ts
@@ -68,7 +68,6 @@ export const coverageConfigDefaults: ResolvedCoverageOptions = {
     '.mjs',
     '.ts',
     '.mts',
-    '.cts',
     '.tsx',
     '.jsx',
     '.vue',
diff --git a/packages/vitest/src/node/cli/cli-config.ts b/packages/vitest/src/node/cli/cli-config.ts
index 02d3755ea40a..055a05387a15 100644
--- a/packages/vitest/src/node/cli/cli-config.ts
+++ b/packages/vitest/src/node/cli/cli-config.ts
@@ -203,7 +203,7 @@ export const cliOptionsConfig: VitestCLIOptions = {
       },
       extension: {
         description:
-          'Extension to be included in coverage. May be specified more than once when using multiple extensions (default: `[".js", ".cjs", ".mjs", ".ts", ".mts", ".cts", ".tsx", ".jsx", ".vue", ".svelte"]`)',
+          'Extension to be included in coverage. May be specified more than once when using multiple extensions (default: `[".js", ".cjs", ".mjs", ".ts", ".mts", ".tsx", ".jsx", ".vue", ".svelte"]`)',
         argument: '<extension>',
         array: true,
       },
diff --git a/test/coverage-test/fixtures/src/should-be-excluded-by-default.cts b/test/coverage-test/fixtures/src/should-be-excluded-by-default.cts
new file mode 100644
index 000000000000..8047d5ad4ce7
--- /dev/null
+++ b/test/coverage-test/fixtures/src/should-be-excluded-by-default.cts
@@ -0,0 +1,7 @@
+/*
+ * Vite does not transform `*.cts` files.
+ * If this file is picked by Istanbul provider, it will make Babel crash on TS syntax.
+ */
+interface Props {
+  name: string;
+}