diff --git a/include/aws/s3/s3.h b/include/aws/s3/s3.h
index 49b9a542..144969d0 100644
--- a/include/aws/s3/s3.h
+++ b/include/aws/s3/s3.h
@@ -49,6 +49,7 @@ enum aws_s3_errors {
     AWS_ERROR_S3_RECV_FILE_ALREADY_EXISTS,
     AWS_ERROR_S3_RECV_FILE_NOT_FOUND,
     AWS_ERROR_S3_REQUEST_TIMEOUT,
+    AWS_ERROR_S3_TOKEN_EXPIRED,
 
     AWS_ERROR_S3_END_RANGE = AWS_ERROR_ENUM_END_RANGE(AWS_C_S3_PACKAGE_ID)
 };
diff --git a/source/s3.c b/source/s3.c
index a5a0d739..08aa1199 100644
--- a/source/s3.c
+++ b/source/s3.c
@@ -52,6 +52,7 @@ static struct aws_error_info s_errors[] = {
     AWS_DEFINE_ERROR_INFO_S3(AWS_ERROR_S3_RECV_FILE_ALREADY_EXISTS, "File already exists, cannot create as new."),
     AWS_DEFINE_ERROR_INFO_S3(AWS_ERROR_S3_RECV_FILE_NOT_FOUND, "The receive file doesn't exist, cannot create as configuration required."),
     AWS_DEFINE_ERROR_INFO_S3(AWS_ERROR_S3_REQUEST_TIMEOUT, "RequestTimeout error received from S3."),
+    AWS_DEFINE_ERROR_INFO_S3(AWS_ERROR_S3_TOKEN_EXPIRED, "Token expired - needs a refresh."),
 };
 /* clang-format on */
 
diff --git a/source/s3_util.c b/source/s3_util.c
index d2dc46d7..1c6aecb8 100644
--- a/source/s3_util.c
+++ b/source/s3_util.c
@@ -682,6 +682,11 @@ int aws_s3_crt_error_code_from_recoverable_server_error_code_string(struct aws_b
         return AWS_ERROR_S3_REQUEST_TIMEOUT;
     }
 
+    if (aws_byte_cursor_eq_c_str_ignore_case(&error_code_string, "ExpiredToken") ||
+        aws_byte_cursor_eq_c_str_ignore_case(&error_code_string, "TokenRefreshRequired")) {
+        return AWS_ERROR_S3_TOKEN_EXPIRED;
+    }
+
     return AWS_ERROR_UNKNOWN;
 }