In the Philippines, the rights of air passengers are primarily protected under Joint Administrative Order No. 1 (JAO 1), series of 2012, otherwise known as the Air Passenger Bill of Rights (APBR). When an airline fails to process a refund within a reasonable timeframe, passengers have specific legal avenues to demand restitution.

1. Statutory Grounds for Refund

Under the APBR and existing Department of Transportation (DOTr) regulations, a passenger is entitled to a refund in several scenarios:

Flight Cancellation by the Air Carrier: If the airline cancels the flight for reasons attributable to the carrier (e.g., technical issues, operational decisions).
Force Majeure/Safety Reasons: Even if a flight is cancelled due to weather or security, if the passenger chooses not to be rebooked, a refund may be sought.
Significant Delays: If a flight is delayed by at least three (3) hours, the passenger may choose to cancel the trip and demand a full refund.
Fare Rules: Refunds for voluntary cancellations depend on the specific terms and conditions of the ticket (e.g., "refundable" vs. "non-refundable" tickets).

2. Prescribed Timelines for Refunds

The law distinguishes between the modes of payment used for the purchase:

Mode of Payment	Prescribed Refund Period
Cash	Should be processed immediately or within a reasonable time upon surrender of the ticket at the counter.
Credit Card	The airline must process the refund request within twenty (20) working days. The actual appearance of the credit on the statement may vary depending on the bank’s billing cycle.

3. The Exhaustion of Administrative Remedies

Before escalating to a formal legal complaint, the passenger must generally follow a "ladder" of dispute resolution:

Step 1: Formal Demand to the Airline

The passenger must first file a formal request through the airline's official customer service channels. It is critical to:

Note the Ticket Number and Booking Reference (PNR).
Keep a record of all communication, including case numbers and timestamps.
Send a formal Demand Letter via registered mail or email if the online portal remains unresponsive.

Step 2: Filing with the Civil Aeronautics Board (CAB)

If the airline fails to act within the prescribed period or denies the refund without valid cause, the primary regulatory body to approach is the Civil Aeronautics Board (CAB).

Process: Complaints can be filed via the CAB’s online portal or in person at their Pasay City office.
Documentation: Attach the ticket, proof of payment, and copies of the ignored demand letters.
Mediation: The CAB typically initiates a mediation process to encourage a settlement between the passenger and the airline.

4. Legal Recourse: Small Claims Court

If administrative intervention by the CAB does not result in a refund, and the amount involved does not exceed PHP 1,000,000.00 (exclusive of interest and costs), the passenger may file a case in the Small Claims Court (Metropolitan or Municipal Trial Courts).

No Lawyers Required: In Small Claims, parties represent themselves; lawyers are not allowed to appear as counsel during the hearing.
Speed: These cases are designed for summary procedure, often reaching a decision in a single hearing.
Basis: The claim is grounded on a breach of contract (the contract of carriage).

5. Relevant Penalties

Airlines found in violation of the Air Passenger Bill of Rights may face administrative fines imposed by the CAB. Under Republic Act No. 776, as amended, the CAB has the authority to penalize carriers for failure to comply with established regulations regarding passenger welfare.

6. Key Evidence Checklist

To ensure a successful complaint, passengers should preserve:

Proof of Purchase: Original e-ticket and official receipt.
Correspondence: Screenshots of chats, emails, and logs of phone calls to customer service.
Airline Notices: Emails or SMS from the airline notifying you of flight cancellations or delays.
Bank Statements: For credit card transactions, a statement showing the original charge and the absence of a reversal.