It is possible to file a European application, in English, and to prosecute the application before the European Patent Office to the grant of a single European patent. All of the European Union countries are members of the European patent, together with some other countries. When filing the application all member countries are automatically included. There are a number of "extension" countries that are not automaticaly included. These can be included by payment of an additional fee for each country.

Whilst the European patent application is prosecuted to grant of a single patent in English, to place the patent into effect in the designated countries it is necessary to file a translation and pay a fee at many of the national patent offices. There is no obligation to ratify a European patent in all countries designated. Whilst this is a significant cost, it occurs at the end of the process and not at the beginning. In contrast a national application in a non English speaking country needs to have a translation filed with the application at the start of the process.

A European application may be made directly or via a PCT application.

Patents in some European countries can be obtained via a PCT application either as a national patent or via a European patent. However there are a number of countries for which protection can only be obtained via a European patent via the PCT route. It is not possible to file a national patent from a PCT application for those countries.