The players must serve five years of their sanctions, with the remaining years deferred by the ICC.
"I have already served two years and eight months (of the ban) and after another two years and four months I can still play," Butt said in the eastern city of Lahore soon after CAS rejected his appeal in Lausanne, Switzerland.
"I wasn't more than 50 percent sure that the decision will come in my favor," he added.
Butt will be 30 when his minimum five-year suspension ends, and with Pakistan test and one-day captain Misbah-ul-Haq at 39, Butt believes he can contend again for a place in the national team.
"If I can perform when the ban ends its fine, otherwise I will have to do some other work," he said.
Lawyers for Butt said the player "will be exploring every other available avenue" to resume his professional career.
"Both Salman and us are bitterly disappointed with the decision of the court," said Amer Rahman, the legal advisor who represented Butt in the appeal. "Salman has been in a very dark place over the last few years and he was hoping that he would be successful in this appeal. We will not be giving up."
Butt, Asif and teammate Mohammad Amir were found guilty in an English criminal trial of arranging to bowl no-balls for betting scams during an August 2010 test at Lord's. They were jailed for three to seven months.
CAS said Butt did not contest the ICC's guilty verdict against him but wanted a reduction in the length of his ban.
"However, the panel was not persuaded that the sanction imposed by the ICC tribunal was disproportionate, nor that any of the mitigating circumstances advanced by Mr. Butt qualified as exceptional circumstances," CAS said in a statement.
Regarding Asif, who didn't appeal his ICC sanction, CAS was "satisfied beyond reasonable doubt that Mr. Asif was party to a spot-fixing conspiracy," and that there was "no evidence advanced ... which clearly exculpated him and that his submissions did not break the chain of circumstantial evidence or in any way undermine the reasoning contained in the ICC's decision."
The same panel of three CAS arbitrators judged both cases after appeal hearings in February. CAS verdicts can be challenged at Switzerland's supreme court, which can overturn decisions only if legal process was abused.
Amir did not appeal in the CAS against his five-year ban.
Pakistan cricket has been constantly hit by fixing charges in recent times, and only last week the Pakistan Cricket Board banned international umpire Nadeem Ghauri for four years over corruption charges.
- AP
