diff --git a/builtin/providers/azurerm/resource_arm_virtual_machine.go b/builtin/providers/azurerm/resource_arm_virtual_machine.go
index e3fe29808..c3f736412 100644
--- a/builtin/providers/azurerm/resource_arm_virtual_machine.go
+++ b/builtin/providers/azurerm/resource_arm_virtual_machine.go
@@ -1033,7 +1033,7 @@ func flattenAzureRmVirtualMachineOsProfileLinuxConfiguration(config *compute.Lin
 	result["disable_password_authentication"] = *config.DisablePasswordAuthentication
 
 	if config.SSH != nil && len(*config.SSH.PublicKeys) > 0 {
-		ssh_keys := make([]map[string]interface{}, len(*config.SSH.PublicKeys))
+		ssh_keys := make([]map[string]interface{}, 0, len(*config.SSH.PublicKeys))
 		for _, i := range *config.SSH.PublicKeys {
 			key := make(map[string]interface{})
 			key["path"] = *i.Path