The National Grid Corporation of the Philippines (NGCP) reported a slight decrease in transmission wheeling rates for the May 2025 billing period, but an increase in Ancillary Services (AS) charges drove up the total average grid-related costs seen in consumers’ June electric bills.

Transmission wheeling rates dropped by 0.27%, from PHP 0.4605/kWh in April to PHP 0.4593/kWh in May — a decrease of PHP 0.0012/kWh.

In contrast, Ancillary Services rates rose by 9.29%, increasing from PHP 0.5175/kWh in April to PHP 0.5655/kWh in May — or a PHP 0.0480/kWh increase.

“As a pass-through cost, AS rates are only collected by NGCP and remitted directly to generation companies,” NGCP clarified.

Ancillary Services, or support services used to balance and stabilize the grid during power supply-demand imbalance, are sourced either from the AS reserve market or from AS providers with bilateral contracts with NGCP.

As a result, the overall average transmission rate (including AS) for the May billing period — reflected in June bills — rose to PHP 1.1482/kWh, up from April’s PHP 1.0978/kWh. This is a 4.60% month-on-month increase.

What’s your take on this rate shift? Share your insights on how Ancillary Service dynamics are shaping power costs in the Philippines.

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