The audit procedure is regulated in the Act on the NIK and in the Regulation of the President of the NIK on Audit Proceedings of 1 March 1995.

Preparation of Audits
The subjects of audits are contained in annual and quarterly work plans, adopted by the Council of the NIK. Audits are performed on the basis of these plans. If necessary, the NIK can undertake ad hoc audits. For audits contained in the periodical work programmes audit programmes are prepared. The programmes must get accepted by the President of the NIK or one of Vice-Presidents.

Auditing Process
The goal of every audit is to establish the facts, that should be properly documented, and to assess them according to the rules as put down in the law. The following criteria must be met for the proper course of audits:
the NIK’ s auditors have access to all information they require for their audit work - they have the right:
To have free access to the premises of audited units, to look into all documents and other materials, to observe the premises, to summon witnesses and receive their evidence, to demand oral or written explanations from employees of audited units, to call experts and specialists, to summon meetings with employees of audited units, to participate in meetings of the management as well as in meetings of bodies of government administration and local self-government.
The final element of a field audit is drawing up an audit report. It should describe the facts established during the audit, including the reasons for their occurrence, the scope and effects of irregularities as well as the persons responsible for them. The audit report should be signed by the auditor and the head of the audited unit.
The auditee may appeal against the findings of the audit.

Appeal Procedure
The head of the audited unit has the right to raise (within 14 days) reservations about the facts contained in the report. The auditor is obliged to analyse these reservations, and, if they prove justified, to change or to amend the report. The auditor submits the amended (or not) report to the head of the unit.If the head of the unit concludes that the auditor did not take into account any or some of their reservations, they may appeal to the director of the relevant NIK's unit.The director appoints members of the appeal committee.The committee adopts a resolution concerning the reservations mentioned and submits it to the President of the NIK. The President may sign the resolution and hand it to the head of the audited unit -then the head of the audited unit has no right to appeal against it. If the President refuses to sign the resolution, he appoints members of the resolution committee. The decision of the resolution committee is final.The decision of the committee is handed to the head of the audited unit.The head of the audited unit has right to refuse to sign the audit report -the auditor notifies it in the report. The evaluation of the audited activity is described in a post-audit statement. If any irregularities are disclosed, the statement may include comments and recommendations aimed at their removal. The post-audit statement may also assess the performance of the persons responsible for the irregularities disclosed and indicate their unsuitability for the positions they occupy. The post-audit statement is submitted to the head of the audited unit. The appeal procedure is applicable now as well.
On the basis of audit reports and post-audit statements the NIK draws up pronouncements on audit results. Before they are submitted to the Sejm, the President of the Republic of Poland or the Prime Minister, they are submitted to the appropriate supreme and central government bodies which within 7 days may present their opinion. The opinion is enclosed with the pronouncement on the results of the audit.