How to use whatsApp with Landline number? How to setup whatsApp for business ? On your mobile’s market store, search for whatsApp Business (Android or iOS). Do the normal whatsApp registration procedures as usual. choose your country code from the menu. Then use your land line number as contact number. (for eg: 6693 5414). Do not use prefix ‘0’ before your contact number. Because the country code is already added. Just use the direct public number only, not any Extensions number. How to