The 20c rise is a 23.5% increase, which is nearly three times the current level of inflation.
The British owned retailer is now even higher than upmarket store Marks and Spencer, which is selling its own brand litre of milk in its Irish stores for 95c.
Several other chains are also selling their own brand litre of milk for 95c – namely Dunnes Stores, Aldi, Lidl and Iceland.
SuperValu’s own brand litre of milk is, like Tesco, also priced at €1.05.
Centra is selling its own brand litre of mile for €1.30, while Eurospar and Spar are selling their version for €1.45.
The highest price we found for own brand litre of milk is Circle K, at €1.60.
Many of the stores also sell Avonmore, which ranges in price from €1.39 to €1.69 a litre.
Dealz does not appear to sell litre version, with a two-litre own brand priced at €1.50
Last year Tesco was selling a litre of milk for 75c, before a rise to 85c and then its new level this week of €1.05.
Earlier this week Tesco announced they would discontinue selling Heinz products over a row with the international food producer over pricing.
Figures this week revealed that grocery price inflation continues to climb, hitting 6.5 % in the 12 weeks to June 12 - the highest level in Ireland since February 2013.
But inflation across the euro area rose to 8.6% in June, according to an initial estimate by the EU's statistical agency Eurostat.
And its estimate for inflation in Ireland was 9.6%, which is higher than many forecasters had predicted.
It has also emerged that Irish shoppers are stumping up nearly a fifth more than the Eurozone average for food – and double the average for alcohol.
Dairy, bread and oils are between 20% and 25% dearer, with fish being only slightly cheaper.
New figures by Kantar predict that rising prices could add €453 to the average annual grocery bill, a figure over €100 higher than that predicted in early May.
According to Kantar, shoppers are taking additional steps to manage their spending at supermarket tills and making three fewer trips to the store on average per month than they were this time last year.
The figures also showed that people are looking for cheaper own brand alternatives as Dunnes and Tesco have seen €8.2m more spent between them on their private label lines.
Dunnes and Tesco are now tied with both holding a 22.1% share of the Irish grocery market.
Tesco also saw a boost of 10% in online sales during the month of June, with shoppers spending an additional €2.9m.
SuperValu now holds 21.7% of the market. Lidl and Aldi follow behind, each accounting for 13.2% and 12.3%.
The online grocery market grew by 9.3% in June, as online channels continue to grow over two years on from the first lockdown.
A spokesperson for Tesco said: “Tesco is a significant supporter of the Irish dairy sector. We work collaboratively with our suppliers to minimise impacts to our customers and offer them the best possible value on products that matter most to them.
“However, commodity price increases, changes to fertiliser and feed costs as well as the impact of global demand can lead to price increases.
“Whilst the retail market is highly competitive, we are committed to consistently delivering great value and we have invested heavily to provide competitively priced products to our customers.”