But tough economic conditions push unit's revenue down by 2.7pc to €1.13bn
Operating profit at Vodafone's Irish arm jumped 12pc to €114.5m in the 12 months to the end of March 2012, newly filed accounts for the company show.
But revenue at the unit was down by 2.7pc to €1.13bn in the period as the company battled with a tough economy and reduced consumer spending.
Vodafone, as with other mobile operators, has seen the average monthly revenue it generates per user (ARPU) consistently decline as it's forced to react to increased competition and subscribers keeping a closer eye on bills.
The accounts also show that Vodafone paid a final dividend of €60m to its UK parent in the financial year. It paid the same amount in the previous financial year. The Irish operation has repatriated a total of about €2.3bn over the past number of years.
Vodafone is Ireland's biggest mobile operator, with 2.2 million customers. About 43pc of those subscribers now use a smartphone. Vodafone also has 242,000 fixed-line and broadband customers here.
The accounts for the last financial year show that ARPU fell 3.4pc to €31.20 in the quarter ended March 2012. In November, Vodafone said that its ARPU in Ireland was static.
"Vodafone performed well over the course of the year despite high customer acquisition costs driven by handset subsidies," directors of the Irish subsidiary note.
They said there had been a 59pc year-on-year rise in the number of smartphones on its network and that it had 1.05 million mobile internet users, up 14pc on the previous year.
In the year to last March, the company spent about €120m on its network.
Vodafone and rival 3 Ireland signed a deal last year that saw them create a joint venture to oversee their network infrastructure. That could save them up to €225m each.
Last November, Vodafone paid nearly €161m upfront to the exchequer to acquire rights to use super-fast 4G spectrum. It will pay an additional €119.7m by 2030.
The latest accounts reveal that Vodafone Ireland's pre-tax profit rose 32pc to €136.8m.
That was helped by €19.1m in interest received, compared with €5.2m in the previous year, lower depreciation and amortisation charges and a decrease in operating costs to €264m from €269m.
Its tax bill fell sharply, from €26.2m to €18.5m. That included corporation tax of €18.4m in the 2012 fiscal year compared with €22.8m a year earlier.
Vodafone employs roughly 1,100 people in Ireland.
In November, the group said its operations in Ireland, Greece, Spain and Portugal remained the "most directly impacted" by tough market conditions.