The 29-year-old Asif, who was jailed in November after being as guilty of conspiring to cheat and conspiring to accept corrupt payments over deliberate no-balls bowled during the Lord's Test against England in August 2010.
The tainted player was released from Canterbury Prison in southeast England on Thursday morning, his London-based law firm SJS Solicitors said.
Asif's lawyer Ravi Sukul told Geo television on Wednesday that he could be extending his stay in England while he can also launch an appeal against his conviction.
"I have a strong belief that if certain procedures had been applied in Asif's benefit at his trial, they could have persuaded the jury to come to a different conclusion," Sukul was quoted as saying by AFP.
Butt is serving his jail term of 30 months while Aamer was released earlier in Febraury after three months in detention.
Bookie Mazhar Majeed, who started the deal, was jailed for 32 months.
The International Cricket Council (ICC) also banned the three players for a minimum of five years. All three players have the right to appeal against the ICC ban in the Swiss-based Court of Arbitration for Sports.