A day after receiving strike authorization from members on its live-action basic cable contract, SAG reached a tentative deal on its animation cable contract.

SAG said Tuesday that the new 2½-year animation pact represents a 20% hike in residuals, based on the typical pattern for animated basic cable episodes of an initial run followed by an average of 25 repeats.

The two sides met informally Tuesday about the basic cable negotiations but cited a news blackout and disclosed no details. Formal bargaining’s expected to resume as early as today in Los Angeles.

Terms of the animation pact — the first improvement to the residuals formula in this contract in 16 years –are similar to the offer SAG recently spurned in basic cable.

However, SAG spokesman Seth Oster stressed that the new animation contract represents a significant boost to performers’ bank accounts, particularly at the bottom rate of 1.5%, since animated episodes tend to run far more often than live action. SAG noted that it’s not uncommon for the most successful animated cable series to rack up more than 100 reruns.

“It really is an apples-to-oranges comparison,” Oster said of the similarity between the live-action offer and the animated deal.

Latter covers such shows as “SpongeBob SquarePants” and “The Boondocks.” If approved by SAG’s national board next month, pact will be retroactive to Jan. 1 and run through June 30, 2008.

Guild also said the deal includes a new “understanding” that all animated production for basic cable done by guild signatories will now be covered by the contract; previous practice was to rely on single-production contracts.

“The performers who work under this contract have waited a long time for these well-deserved gains, particularly in the area of residuals,” SAG prexy Alan Rosenberg said. “Thanks to the hard work of the negotiating committee and staff, and with the support of our membership, we were able to improve this contract, which affects mainly working day performers, for the first time in almost two decades.”

Terms of the animated deal would increase residual rates from the current 12% to 17% of the minimum (currently $716 for a four-hour session), going down to 1.5% of the minimum for the 13th showing and each subsequent run.

SAG’s negotiating committee on the animated pact, led by Loren Lester, didn’t seek strike authorization. At the member caucus last month, negotiators told members they were confident subsequent talks would lead the companies to improve their offer of 1% for the 13th run and beyond.

Guild will hold a caucus April 10 in Hollywood for members to review the animated agreement before it goes to the national board for ratification at its April 21-22 meeting.

SAG must ratify the pact by April 30 for it to take effect.