Member States shall establish cost bases for charges for each charging zone in a transparent manner.

At the latest four months before the start of the reference period, Member States shall, in a coordinated manner, consult air navigation service providers, airspace users' representatives, and, where relevant, airport operators and airport coordinators on the intended establishment of the determined costs included in the cost base for en route and terminal charges, new and existing investments, service unit forecasts and charging policy for the reference period concerned.

Member States shall also do so during a reference period, where they intend to request a revision of performance targets in the key performance area of cost-efficiency in accordance with Article 18(1).

Member States shall provide the reporting tables and the information required in Annexes VII and IX to the entities invited to the consultation at least three weeks before the consultation.

During the reference period, Member States shall on an annual basis, in a coordinated manner, and in accordance with point 1 of Annex XII, consult air navigation service providers, airspace users' representatives, and, where relevant, airport operators and airport coordinators on the actual costs incurred during the previous year and the difference between the actual costs and the determined costs contained in the performance plan.

Member States shall provide the reporting table and information required in Annex VII to the entities invited to the consultation at least three weeks before the consultation.

Member States shall provide the information referred to in the last subparagraph of paragraphs 2 and 3 to the Commission at the date when it is provided to the consulted parties. Member States shall also inform the Commission about the outcome of the consultation.