The former Spain international will embark on his first spell abroad, signing for the Mexican club, who are led by Real Madrid legend Hugo Sanchez
The former Spain international will join Pachuca after 16 years in his home country, starring mostly for Espanyol, where he scored more than 130 goals.
Tamudo's agent was reportedly close to sealing a deal with Puebla a week ago, as the 18 first division clubs met in Cancun for the domestic transfer deadline day. Puebla had signed fellow Spaniard Luis Garcia in 2011.
After the deal with the Camoteros fell through, Pachuca entered the fray, and the former Real Sociedad and Rayo Vallecano striker will now make his way to the North American country.
Tamudo, 34, was part of the 2000 Olympic squad that captured the silver medal in Sydney. He scored five times in 13 matches for La Roja.
At Espanyol, Tamudo was one of the team's biggest stars from 1996 to 2010, winning a pair of Copa del Rey trophies in 2000 and 2006.
Pachuca have already made one of the biggest splashes over the summer in the Mexican market, signing Real Madrid legend Hugo Sanchez as the club's coach as well as entering negotiations for Nery Castillo.