All internally invoiced costs must be directly measurable and verifiable and must be broken down into budget categories. It is not possible to charge internal costs as global costs covering several budget categories (all-in average costs). Contrary to the 7th Framework Programme, it is also not possible to charge average costs. Internally invoiced costs may not include indirect costs or a profit margin or mark-up.
The use of the invoiced goods and services for the project and the time of use must be documented. An "internal invoice" is not necessary, but the beneficiary must document the methodology of calculation (which must be part of the usual cost accounting practice of the beneficiary).
Please also note that the hourly rate for internally invoiced personnel costs must be calculated according to the Horizon 2020 rules and the staff concerned must keep compliant time records ("time sheets").
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