Girls' Generation

During their early career, the group were endorsers for several brands such as Elite Uniform, Nexon Bubble Fighter, Samsung and LG. Since 2008 they have been exclusive models for the Goobne Chicken and have filmed several commercials for the brand, recorded jingles for advertising purposes, and modeled for promotional Goobne calendars as well. Goobne Chicken has since become a strong contender in the chicken industry and attribute their success to the group. By mid-2009 the group members were models for over 10 brands and were chosen as one of South Korea's most sought after advertisers in a survey conducted by brand consulting research institute. Several members are solo advertising models such as Seohyun who is a model for Clean and Clear and The Face Shop, Taeyeon who models for A-Solution, a cosmetics brand, Sooyoung, Tiffany and Yuri as models for Biotherm or Yoona who models for S-Oil and Innisfree. Alongside Super Junior, they are also exclusive models to the partly SM Entertainment-owned retail brand SPAO. Endorsing clothing brands, online games, food industries, events, electronics, cosmetics and even products reserved for the top celebrities to endorse such as petroleum and credit cards, the group was considered one of the most sought after models in 2009.

The group continued to be active in advertising in 2010, endorsing brands and products including the Nintendo DSi and Domino's Pizza. In late 2010, a gift certificate company began releasing gift certificates each worth 10,000 won which featured Girls' Generation images on the cards, making them the first celebrities to be featured as such. The Korean web portal Daum also began using the group as models while remodeling certain services and search engines in early October 2010, and released Girls' Generation desktop wallpapers and screensavers for promotion. A survey conducted in December 2010, saw 409 out of 741 marketing employees choosing Girls' Generation as the model with the most influence over consumers, attributing their positive attention from the public to their vocals, looks and fashion sense. In 2011, Intel Asia announced that the group would become official advertising models for the company.

Meanwhile, members Yuri, Jessica, Tiffany, Sooyoung, Sunny and Hyoyeon were models for Christian Dior. Other members which include Yoona, Seohyun and Taeyeon were not models for Christian Dior, due to their other cosmetic contracts. Woongjin Coway stated that they selected Girls' Generation as their exclusive models and recently contracted with the group to endorse their water purifiers. Their contract will begin on March 1 and last through the year, while TV advertisements will begin running mid-March. In March 2011, the group started endorsing the Vita500 brand of energy drinks as part of Vita500's 10th anniversary and exclusive Vita500 posters of Tiffany, Yuri and Yoona were released.

In Japan, the group is currently endorsing the throat lozenge brand E-ma Nodoame. They endorsed Lipton tea as well, with their songs "Let It Rain" and "MR. TAXI" used as background music. In July 2011, along with labelmates TVXQ, they started endorsing 7-Eleven Japan products featuring the Japanese version of the song "Hoot" in commercials.

On August 19, 2011, Girls' Generation were chosen as the ambassadors for the 2010-2012 Visit Korea Year. Seohyun will be appointed as UNICEF envoys on October 11, 2011 at Changseong-Dong, Seoul. This is a notable feat, as only those who have a respectable reputation are appointed as goodwill representatives.

On October 2011 Girls' Generation were appointed models for J.ESTINA.