Irish prisoners got a 10pc increase in pocket money last year as more than €2.8m of taxpayers' cash was doled out.
Every inmate receives a "daily gratuity" that can be used to buy computer games, confectionery and tobacco.
Last year, the total gifted to criminals in Irish jails increased by €268,867 to €2,864,885.
Before 2012, all inmates were entitled to a flat rate of €2.35 per day.
An incentivised regime was then introduced, allowing pocket money to be increased or reduced depending on a prisoner's behaviour.
A standard daily rate of €1.70 now applies but this can be increased to €2.20 if a prisoner is compliant, or reduced to a basic rate of 95c if a prisoner misbehaves.
The proportion of inmates on the basic rate increased from 9pc to 11pc last year, having stood at just 7pc in 2016, according to records released under the Freedom of Information Act.
However, the number of prisoners on the enhanced rate also climbed, from 46pc to 48pc. Some 41pc of prisoners were on the standard rate last year, compared to 45pc in 2017.
Inmates can earn an additional €3.50 a week by mucking in with chores such as painting, cleaning, cooking, ground maintenance, laundry and waste management.
It can be spent on discretionary items such as toiletries and tobacco from the tuck shop, as well as paying for television rental or other services offered by the Irish Prison Service (IPS). It can also be saved until a prisoner is released.
Inmates at Shelton Abbey in Co Wicklow, who were given €73,892 last year, can also spend their money in the high street as the institution is an open prison from which detainees can come and go.
Detainees can also apply for interest-free loans from the prison service and repay the borrowings using their daily gratuities.
A total of €500,000 was loaned to prisoners between 2014 and 2016 for a variety of purposes, including buying games consoles and stereos.
Last year, the highest amount of pocket money was paid out by Midlands Prison in Portlaoise, which houses notorious killers Graham Dwyer and Mark Nash. It gave €604,742 to its inmates, compared to €570,470 in 2017.
The amount paid to inmates in Mountjoy Prison increased by 26pc last year, climbing to almost €500,000 in 2018 from €396,328 the previous year.
The IPS said the incentivised scheme "provided tangible incentives to prisoners to participate in activities and reinforce good behaviour, leading to a safer, more secure environment".