A halal certificate is needed to sell edibles to Muslims. If you do not have a halal certificate, Muslims will not buy from you since they only eat halal foods. In order to ensure your Muslim customers that you really sell halal food that they can eat, you have to have a halal certificate. There is no other option.
For restaurants in Singapore, it is not necessary to get a halal certificate. You can run a restaurant without one but you cannot sell food to Muslims. Even if you try, they will not eat.
This will reduce the size of your target market and will impact sales. If you intend to increase sales and to target Muslims, you must get a halal certificate. It is not hard. You can apply for a certificate with the local authority, they will do a halal audit, and if your restaurant follows all the procedures, you will most likely get the certificate.
No hard and fast rules.
Since majority of the people in Singapore are Muslims, therefore, it is a smart move to apply for a halal certificate. It is useless to have a restaurant where Muslims cannot eat especially when your restaurant is in a Muslim majority place.
Apply for halal certification today.