registration number
A unique number assigned when something is officially registered, such as a vehicle, company, or product.
Please note down the vehicle registration number.
Please tell me the registration number of this car.
The new company obtained a registration number from the tax office.
Please check the registration number of the product before purchasing.
Once the application is accepted, a registration number will be issued.
識別番号 is a general term for any unique identifying number, while 登録番号 specifically refers to a number assigned upon official registration.
製造番号 is the serial number a manufacturer assigns during production, whereas 登録番号 is issued by an authority when the item or entity is formally registered.
license plate (for registered vehicles, compact car or larger)
Compound of 登録 (registration) + 番号 (number).