Stephen Cavanagh, 32, of Byron Road, Denton, was on remand at HMP Manchester when he complained of stomach pains.
An X-ray revealed the phone, which he later ejected from his body to flush down the toilet.
HMP Manchester governor Terri Williams, said the case highlighted the "extreme measures" used to bring "illicit items" into the jail.
Greater Manchester Police work with prison staff to prosecute offenders who try to smuggle in forbidden items, she said.
"It is now clear that prisoners are likely to be given additional time in custody following successful prosecutions," she added.
The Ministry of Justice refused to give any further information on when or how the phone was inserted into  Cavanagh's body.
A prisoner who smuggled a mobile phone up his backside into a prison has had his sentence extended.