Taco Bell's $2 burritos and $1.49 breakfast offerings attracted more low-income consumers looking for cheaper options amid decades-high inflation, while wealthier customers looking to save also increased orders from Yum's outlets.

"We are seeing higher income customers coming more frequently. And some of that is no doubt due to trade down into our brands," Yum's Chief Executive Officer David Gibbs said on an earnings call.

The launch of "Melts" - an individual-sized meal consisting of two slices of pizza and dipping sauce - at Pizza Hut and value deals on wraps at KFC also helped drive traffic. Both brands reported a rise in U.S. same-store sales but weak China sales led to a miss on Wall Street estimates.

"(Same-store sales) would have missed overall if not for the big upside at Taco Bell... The China business has been weighing on the results as well," said Edward Jones analyst Brian Yarbrough.

Yum's shares were last up marginally in choppy trading.

At Taco Bell, which also re-launched the cult-classic Mexican Pizza in September, same-store sales surged 11%, crushing analysts' estimate for a 6.8% rise.

"Taco Bell remains the crown jewel in Yum's portfolio," Cowen analyst Andrew Charles said.

Total same-store sales at Louisville, Kentucky-based Yum rose 6% for the three months ended Dec. 31, while analysts had expected a 4.57% increase.

Yum also took a 2-point hit to profit from the move to exit Russia.

Excluding items, the company earned $1.31 per share in the fourth quarter, beating estimates of $1.26, according to Refinitiv IBES data.