An online coupon for free shipping at Kohl’s and a printable coupon for 20% off a total purchase at Gap were the most popular coupons for the second straight month in January 2010, according to coupon aggregator RetailMeNot, which recently released its coupon data report for the month. (via MarketingCharts).

January 2010 coupon traffic measured 14.68 million users, a 61% increase from 9.1 million users in January 2009. During the month, online coupon users generated about $34 million in sales, a 61% jump from $21.1 million in January 2009. There were 376,090 online coupons available for 58,667 retailers, and 58,667 printable coupons available for 52,000 stores.

Victoria’s Secret, Amazon and Domino’s were the three most-searched stores for online coupons. Domino’s replaced Best Buy, which slipped to ninth place, in the number three spot. Fantastic Sam’s, Dave and Buster’s, and Kentucky Fried Chicken were the top three searched printable brands.