Spanish commercial broadcaster Telecinco posted record net profits of E290.3 million ($346.4 million) in 2005, up 35.5% on 2004 on full year revenues up 17% to $1.11 billion, another record.

Telecinco’s standout perf played off its usual cost containment, its 22.3% all-day audience share, the best of any broadcaster in Spain for 2005, and a booming TV ad market.

But while total TV ad revs increased 10.2%, Telecinco posted a 15.7% gain in TV advertising pushing total net ad sales to $1.04 billion.

Telecinco spent just $183.7 million on acquisitions for 2005, underscoring Telecinco’s tight financial ship.

“Telecinco has always been very concerned about controlling costs. It doesn’t like expensive events that don’t drive profitability, like soccer,” said Luis Fananas at Deutsche Bank.

This year is likely to be tougher with both Telecinco and rival Antena 3 under sound, profits-fixated management.

Though neither will notch up ratings at any cost, high audience share will inevitably affect their bottom line.

Antena 3 took 21.9% to Telecinco’s 20.7% in January, partly thanks to the last episodes of A3-aired telenovela “Pasion de gavilanes” (Hidden Passion).

But on the back of its primetime fiction, led by “CSI: Miami” and vet Spanish cop show “Police Commissioner,” Telecinco clawed back share to claim 20.8% to Antena 3’s 21.1% last month.