The system formerly utilized the "Flash Pass", a pass for use on all three rapid transit lines in the Metro Manila area (the Yellow, Purple and Blue Lines). The pass costs 250 pesos and may be used for multiple rides on any of the metro lines for one week. The system was introduced on April 19, 2004.

A Flash Pass consists of two parts: a card, known as a Flash Pass Card, and a ticket, known as a Flash Pass Coupon. Both components are complementary: a Flash Pass Card is issued when buying a Flash Pass Coupon for the first time, and a Flash Pass Coupon must be used with its corresponding Flash Pass Card. The one-week validity period of a Flash Pass Coupon only corresponds to the Flash Pass Coupon, since a Flash Pass Card does not expire.

It was believed that the Flash Pass was a precursor to a unified ticketing system utilizing contactless smart cards, similar to the Octopus card in Hong Kong and the EZ-Link card in Singapore. However, this project has since been dropped. Instead, passengers simply show their Flash Pass coupon to the gatekeeper who will manually open the gate once validated.