Inmates in the country's largest jail - the Midlands Prison - received nearly €871,000.
Irish prisoners were paid more than €2.5 million in pocket-money in the first ten months of last year.
The details have been released under the Freedom of Information Act.
There are more than 4,000 prisoners in 13 jails across the state.
Every inmate receives a daily allowance from the Irish Prison Service, which they can spend to buy items in the tuck shop.
The standard daily rate is €1.70 but this rises to €2.20 for well-behaved prisoners and is cut to 95 cent for bad behaviour.
Inmates can also get additional payments of up to 3.50 per week for working in areas such as prison kitchens or laundries.
John Lonergan, a former governor of Mountjoy and Portlaoise Prisons, says the daily allowances are far too low:
In all of last year, prisoners received a further €4.35 million in gifts from family and friends.
Inmates in the country's largest jail - Midlands Prison - received nearly €871,000, while those in Mountjoy Prison - the second biggest - got more than €805,000.