Most EU programmes require own funds to get a project approved by the EU. This means that the approved project total budget is made up of co-financing by the EU and a capital share. The level of co-financing is subject to the respective programme and call specifications. A 100% co-financing is very rarely granted.
The share capital (thus the difference to the project budget and co-financing) can be carried out depending on the programme and call preset from own resources of the promoter or from third-party funds (eg a public body). Own work (eg staff costs which can not be claimed for people who work in the project) are also possible in some cases.