Tiffany said sales in November and December rose in every region of the world where it operates jewelry stores, jumping 11 percent overall to $888.5 million.

Signet, which also operates the more modestly priced Kay Jewelers chain in the United States and H.Samuel in Britain, said sales at its U.S. stores open at least a year rose 11.7 percent.

At its Jared chain, which accounts for about a quarter of sales and where the average item is more than twice as expensive as at Kay, same-store sales jumped 20.1 percent.

"The higher tier consumer is definitely back," said Joel Bines, a managing director at AlixPartners' retail practice. "Consumers with money to spend are not afraid to splurge right now."

Last week, top U.S. retailers reported same-store sales gains of 3.1 percent, coming in slightly under Wall Street forecasts. Upscale chains such as Nordstrom Inc and Saks Inc reported some of the best results.

Industrywide, the holiday season that runs between Thanksgiving and New Year's accounts for 29.5 percent of annual jewelry sales in the United States.

Tiffany's sales rose most sharply in Asia, excluding Japan, soaring 23 percent to $138.9 million. In North and South America, they were up 9 percent at $484.8 million, including a 3 percent rise at Tiffany's flagship store on Manhattan's Fifth Avenue.

Tiffany sales continued to climb in Europe, gaining 13 percent. Sales even rose in Japan, where results have languished in recent quarters, jumping 3 percent after factoring currency exchange rate changes.

Tiffany said it was on track to reach sales of $3.1 billion for the current fiscal year.

Citing strong holiday results, Tiffany raised the range of its profit forecast for the fiscal year ending Jan. 31 by 11 cents on both ends, to net earnings from continuing operations of between $2.83 and $2.88 per share, compared to Wall Street forecasts of $2.78 per share, according to Thomson Reuters I/B/E/S.

Signet said its expects income before income tax to be up between 25 percent and 31 percent this fiscal year and expects adjusted earnings per share between $2.54 and $2.66.

Signet results were bogged down by a 4.2 percent same-store sales decrease at its British chains, which make up for 20 percent of its business.

Tiffany shares were up 3 percent in premarket trading.