diff --git a/.changeset/neat-eels-count.md b/.changeset/neat-eels-count.md
new file mode 100644
index 0000000..540dfad
--- /dev/null
+++ b/.changeset/neat-eels-count.md
@@ -0,0 +1,5 @@
+---
+"@gelatocloud/gasless": patch
+---
+
+refactor: use authorization header for auth
diff --git a/src/bundler/index.ts b/src/bundler/index.ts
index 8518480..843fafc 100644
--- a/src/bundler/index.ts
+++ b/src/bundler/index.ts
@@ -77,7 +77,7 @@ export const createGelatoBundlerClient = async (
   const transport = http(endpoint, {
     fetchOptions: {
       headers: {
-        'X-API-Key': apiKey,
+        Authorization: `Bearer ${apiKey}`,
         ...parameters.httpTransportConfig?.fetchOptions?.headers
       },
       ...parameters.httpTransportConfig?.fetchOptions
diff --git a/src/relayer/evm/index.ts b/src/relayer/evm/index.ts
index 5a8565e..2a208a2 100644
--- a/src/relayer/evm/index.ts
+++ b/src/relayer/evm/index.ts
@@ -78,7 +78,7 @@ export const createGelatoEvmRelayerClient = (
     ...parameters.httpTransportConfig,
     fetchOptions: {
       headers: {
-        'X-API-Key': apiKey,
+        Authorization: `Bearer ${apiKey}`,
         ...parameters.httpTransportConfig?.fetchOptions?.headers
       },
       ...parameters.httpTransportConfig?.fetchOptions
diff --git a/src/version.ts b/src/version.ts
index 30ae1a5..7df34a4 100644
--- a/src/version.ts
+++ b/src/version.ts
@@ -1 +1 @@
-export const version = '0.0.9';
+export const version = '0.0.11';