## Interest on late payment II.23.3. 

If the contractor does not honour the obligation to pay the amount due by the date set by the contracting authority in the debit note, the amount due bears interest at the rate indicated in Article II.21.8. Interest on late payments will cover the period starting on the day after the due date for payment and ending on the date when the contracting authority receives the full amount owed. 

Any partial payment is first entered against charges and interest on late payment and then against the principal amount. 

## Recovery rules in the case of joint tender II.23.4. 

If the contract is signed by a group (joint tender), the group is jointly and severally liable under the conditions set out in Article II.6 (liability). The contracting authority shall send the debit note first to the leader of the group. 

If the leader does not pay by the due date the whole amount, and if the amount due cannot be offset or can only be offset partially in accordance with Article II.23.2 (a), then the contracting authority may claim the amount still due to any other member or members of the group by respectively notifying  them with a debit note in conformity with the provisions laid down in Article II.23.2. 

## CHECKS AND AUDITS II.24. 

II.24.1  The contracting authority and the European Anti-Fraud Office may check or require an audit on the performance of the contract . This may be carried out either by OLAF’s own staff or by any outside body authorised to do so on its behalf. 

Such checks and audits may be initiated at any moment during the performance of the contract and up to five years starting from the payment of the balance. 

The audit procedure is initiated on the date of receipt of the relevant letter sent by the contracting authority. Audits are carried out on a confidential basis. 

II.24.2  The contractor must keep all original documents stored on any appropriate medium, including digitised originals if authorised under national law, for a period of five years starting from the payment of the balance. 

II.24.3  The contractor must grant the contracting authority’s staff and outside personnel authorised by the contracting authority the appropriate right of access to sites and premises where the contract is performed and to all the information, including information in electronic format, needed to conduct such checks and audits. The contractor must ensure that the information is readily available at the moment of the check or audit and, if so requested, that information is handed over in an appropriate format. 

II.24.4  On the basis of the findings made during the audit, a provisional report is drawn up. The contracting authority or its authorised representative must send it to the contractor, who has 30 days following the date of receipt to submit observations. The 

