ISO and ITU propose some classifications regarding the smart sustainable cities services: energy, transport, health, tourism, education, safety, environment, governance, commerce, buildings, community. Culture and heritage is a rare category in these classifications, despite the fact they have to be always been included in an SSC ecosystem. They could play a key role in achieving the 17 SDGs due to some critical reasons: their deep roots in humanity, their wide spread across city life and environment, hence their horizontal connections with all the other SSC categories. There are many options of SSC structures, which have the potential to be dedicated on culture and heritage. QR codes, GIS., VR, apps, IoT, virtual events are some of them, widely implemented by cities. Via these ways, culture and heritage could 1) contribute to the humans' welfare index and 2) interact with the other sectors of the city ecosystem. Their added value to the sustainability process creates the necessity to be a distinctive category in international SSC classifications.