diff --git a/.changeset/legal-mugs-care.md b/.changeset/legal-mugs-care.md
new file mode 100644
index 000000000000..5180aef321bd
--- /dev/null
+++ b/.changeset/legal-mugs-care.md
@@ -0,0 +1,5 @@
+---
+"@biomejs/biome": minor
+---
+
+Added support for `.graphqls` files. Biome can now format and lint GraphQL files that have the extension `.graphqls`
diff --git a/crates/biome_cli/tests/commands/format.rs b/crates/biome_cli/tests/commands/format.rs
index 11b145b949ba..bbe517d831df 100644
--- a/crates/biome_cli/tests/commands/format.rs
+++ b/crates/biome_cli/tests/commands/format.rs
@@ -157,6 +157,21 @@ const APPLY_BRACKET_SAME_LINE_AFTER: &str = r#"<Foo
 	reallyLongAttributeName2={anotherLongValue}>
 	Hi
 </Foo>;
+"#;
+
+const SPACING_GRAPHQLS_SANITY_BEFORE: &str = r#"  scalar Time
+  scalar UUID
+
+
+ type   User   {
+  id:  UUID!
+   name: String!
+    updatedAt: Time!
+ }
+
+
+
+
 "#;
 
 const APPLY_ATTRIBUTE_POSITION_BEFORE: &str = r#"<Foo className={style}	reallyLongAttributeName1={longComplexValue}
@@ -3364,6 +3379,31 @@ fn should_error_if_unchanged_files_only_with_changed_flag() {
     ));
 }
 
+#[test]
+fn can_format_graphphs_files() {
+    let fs = MemoryFileSystem::default();
+    let mut console = BufferConsole::default();
+
+    let file_path = Utf8Path::new("file.graphqls");
+    fs.insert(file_path.into(), SPACING_GRAPHQLS_SANITY_BEFORE.as_bytes());
+
+    let (fs, result) = run_cli(
+        fs,
+        &mut console,
+        Args::from(["format", "--write", file_path.as_str()].as_slice()),
+    );
+
+    assert!(result.is_ok(), "run_cli returned {result:?}");
+
+    assert_cli_snapshot(SnapshotPayload::new(
+        module_path!(),
+        "can_format_graphphs_files",
+        fs,
+        console,
+        result,
+    ));
+}
+
 #[test]
 fn applies_custom_bracket_spacing_for_graphql() {
     let fs = MemoryFileSystem::default();
diff --git a/crates/biome_cli/tests/snapshots/main_commands_format/can_format_graphphs_files.snap b/crates/biome_cli/tests/snapshots/main_commands_format/can_format_graphphs_files.snap
new file mode 100644
index 000000000000..3408377e2164
--- /dev/null
+++ b/crates/biome_cli/tests/snapshots/main_commands_format/can_format_graphphs_files.snap
@@ -0,0 +1,23 @@
+---
+source: crates/biome_cli/tests/snap_test.rs
+expression: redactor(content)
+---
+## `file.graphqls`
+
+```graphqls
+scalar Time
+scalar UUID
+
+type User {
+	id: UUID!
+	name: String!
+	updatedAt: Time!
+}
+
+```
+
+# Emitted Messages
+
+```block
+Formatted 1 file in <TIME>. Fixed 1 file.
+```
diff --git a/crates/biome_graphql_syntax/src/file_source.rs b/crates/biome_graphql_syntax/src/file_source.rs
index 994d50ebd37a..173c783843e5 100644
--- a/crates/biome_graphql_syntax/src/file_source.rs
+++ b/crates/biome_graphql_syntax/src/file_source.rs
@@ -36,10 +36,13 @@ impl GraphqlFileSource {
     }
 
     /// Try to return the GraphQL file source corresponding to this file extension
+    /// See the difference between .graphql and .graphqls files here:
+    /// https://www.apollographql.com/docs/kotlin/essentials/file-types#sdl-schemas-graphqls
+    /// https://graphql.com/learn/schema/#inspecting-the-schema
     pub fn try_from_extension(extension: &str) -> Result<Self, FileSourceError> {
         // We assume the file extension is normalized to lowercase
         match extension {
-            "graphql" | "gql" => Ok(Self::default()),
+            "graphqls" | "graphql" | "gql" => Ok(Self::default()),
             _ => Err(FileSourceError::UnknownExtension),
         }
     }
@@ -52,7 +55,7 @@ impl GraphqlFileSource {
     /// [VS Code spec]: https://code.visualstudio.com/docs/languages/identifiers
     pub fn try_from_language_id(language_id: &str) -> Result<Self, FileSourceError> {
         match language_id {
-            "graphql" | "gql" => Ok(Self::default()),
+            "graphqls" | "graphql" | "gql" => Ok(Self::default()),
             _ => Err(FileSourceError::UnknownLanguageId),
         }
     }