1999

In 1998 , Hamasaki’s debut single under Avex, poker face, was released. The single hit the Oricon charts at number 22 and sold 43,000 copies. Hamasaki's third single, Trust, peaked at number nine on the Oricon charts, earning Hamasaki her first song in the Top Ten. Depend on You, Hamasaki's fifth single, was the main theme of video game Thousand Arms. She got her first number-one spot on the charts with her debut album A Song for XX, released on January 1, 1999. A Song for XX held the top spot for a total of five weeks and quickly became certified platinum.

Hamasaki's first number-one single came in 1999 with the release of her seventh single, Love —Destiny—, a song produced by Tsunku. Since the release of Boys & Girls, the ninth, her singles appeared on 12 cm rather than 8 cm discs, following the music-industry trend of moving to media that could hold more data. As a result her singles began to feature more, remix tracks. In its first week, Boys & Girls did not reach the top of the Oricon charts, but it did in its second week, eventually going on to become Hamasaki’s first certified million-seller.

As of November 2007, Hamasaki's 10th single, A, is her best-selling single with more than 1.6 million copies sold. . In November 1999, Hamasaki released her second album, Loveppears, less than a year after her first. The album sold over 2 million copies. The single appears was released the same day. Following the release of Loveppears, two recut singles from the album were released, Kanariya (which became the first recut single in Oricon history to hold the top position on the weekly charts), released in December, and Fly High, released in March 2000.


2000: Duty
Main article: Duty (album)
In 2000, Hamasaki became a spokeswoman for Kos?, a Japanese cosmetics company. When she appeared in commercials to promote Kos?'s lipsticks, a record 500,000 lipsticks were sold in only two days. Her single Vogue, which was used as background music, also benefited from the commercial, selling over 700,000 copies. She also became a spokesperson for Tu-Ka, a now defunct mobile phone carrier, and promoted the company's cell phones.

From April to June 2000, Hamasaki released three singles, Vogue, Far Away, and Seasons. In September, Hamasaki released her third full-length studio album, Duty. As with her previous studio albums, Duty topped the charts and went on to sell 3 million copies, making it her best-selling original studio album. On the same day, the limited pressing single, Surreal and her Ayumi Hamasaki Concert Tour 2000 A were released, both topping the charts in the singles and DVD charts respectively. These three same-week releases made her the first artist to top three charts on the same week