diff --git a/lib/stores/DataStore.js b/lib/stores/DataStore.js
index b87fbaa7..4f95e895 100644
--- a/lib/stores/DataStore.js
+++ b/lib/stores/DataStore.js
@@ -106,6 +106,27 @@ class DataStore extends EventEmitter {
             return resolve({ size: 0, upload_length: 1 });
         });
     }
+
+    /**
+     * Parses the Base64 encoded metadata received from the client.
+     *
+     * @param  {String} metadata_string tus' standard upload metadata
+     * @return {Object}                 metadata as key-value pair
+     */
+    _parseMetadataString(metadata_string) {
+        const kv_pair_list = metadata_string.split(',');
+
+        return kv_pair_list.reduce((metadata, kv_pair) => {
+            const [key, base64_value] = kv_pair.split(' ');
+
+            metadata[key] = {
+                encoded: base64_value,
+                decoded: Buffer.from(base64_value, 'base64').toString('ascii'),
+            };
+
+            return metadata;
+        }, {});
+    }
 }
 
 module.exports = DataStore;
diff --git a/lib/stores/GCSDataStore.js b/lib/stores/GCSDataStore.js
index 7265d429..6008221b 100644
--- a/lib/stores/GCSDataStore.js
+++ b/lib/stores/GCSDataStore.js
@@ -92,7 +92,9 @@ class GCSDataStore extends DataStore {
 
             const file = new File(file_id, upload_length, upload_defer_length, upload_metadata);
             const gcs_file = this.bucket.file(file.id);
+            const parsedMetadata = this._parseMetadataString(upload_metadata);
             const options = {
+                contentType: parsedMetadata.type.decoded,
                 metadata: {
                     metadata: {
                         upload_length: file.upload_length,
@@ -131,9 +133,11 @@ class GCSDataStore extends DataStore {
             return new Promise((resolve, reject) => {
                 const file = this.bucket.file(file_id);
 
+                const parsedMetadata = this._parseMetadataString(data.upload_metadata);
                 const options = {
                     offset,
                     metadata: {
+                        contentType: parsedMetadata.type.decoded,
                         metadata: {
                             upload_length: data.upload_length,
                             tus_version: TUS_RESUMABLE,
diff --git a/lib/stores/S3Store.js b/lib/stores/S3Store.js
index e2c268c2..9dfc1668 100644
--- a/lib/stores/S3Store.js
+++ b/lib/stores/S3Store.js
@@ -233,27 +233,6 @@ class S3Store extends DataStore {
             });
     }
 
-    /**
-     * Parses the Base64 encoded metadata received from the client.
-     *
-     * @param  {String} metadata_string tus' standard upload metadata
-     * @return {Object}                 metadata as key-value pair
-     */
-    _parseMetadataString(metadata_string) {
-        const kv_pair_list = metadata_string.split(',');
-
-        return kv_pair_list.reduce((metadata, kv_pair) => {
-            const [key, base64_value] = kv_pair.split(' ');
-
-            metadata[key] = {
-                encoded: base64_value,
-                decoded: Buffer.from(base64_value, 'base64').toString('ascii'),
-            };
-
-            return metadata;
-        }, {});
-    }
-
     /**
      * Uploads a part/chunk to S3 from a temporary part file.
      *