diff --git a/internal/definitions/service/ntp_server.go b/internal/definitions/service/ntp_server.go
new file mode 100644
index 0000000..513da23
--- /dev/null
+++ b/internal/definitions/service/ntp_server.go
@@ -0,0 +1,6 @@
+package service
+
+type NTPServer struct {
+	Interface string `json:"interface"`
+	Comment   string `json:"comment,omitempty"`
+}
diff --git a/internal/definitions/service/service.go b/internal/definitions/service/service.go
index 109947b..7b56e75 100644
--- a/internal/definitions/service/service.go
+++ b/internal/definitions/service/service.go
@@ -4,4 +4,5 @@ type Service struct {
 	DHCPv4Servers []DHCPv4Server `json:"dhcp_v4_servers" validate:"required,dive"`
 	DHCPv6Servers []DHCPv6Server `json:"dhcp_v6_servers" validate:"required,dive"`
 	DNSServers    []DNSServer    `json:"dns_servers" validate:"required,dive"`
+	NTPServers    []NTPServer    `json:"ntp_servers" validate:"required,dive"`
 }