If you are selling or buying a vehicle in Singapore, record the transfer with a Bill of Sale. However, to actually register the transfer of a vehicle, the Land Transport Authority (LTA) usually requires the use of another prescribed form. The BOS can be used as evidence of the sale, but it is not a replacement for the LTA's prescribed form or official process.
Think of creating a Bill of Sale as a preliminary step in the sale process before registering the actual sale with the LTA. The LTA allows registration to occur up to seven days after a sale.
In addition to a Bill of Sale and any prescribed forms from the LTA, a buyer needs a Certificate of Entitlement (COE) to register a vehicle in Singapore. A COE is a licence that gives you the right to own and use a vehicle on the road. If the previous owner already had the vehicle registered, it will have a Certificate of Entitlement (COE) and it will transfer with the car during the sale.
A COE only lasts for 10 years before it must be renewed or the vehicle must be deregistered. If you are considering buying a car from a private seller, consider the years left on the COE when deciding. The more years left on a COE the better.
If you buy a vehicle that is not registered, you will need to bid for a COE before you will be able to register the car. This bidding process occurs twice a month. Consult the LTA for more information on COE bidding. A COE can be quite expensive, so be sure to consider this when determining the price of the car.