Pay as you go customers on O2 are set to receive compensation following the disruptions experienced earlier this month.
The firm said it recognised the "unprecedented" technical problems had inconvenienced many people during the one-day period when many services were unavailable.
Therefore, it stated: "We are giving them the equivalent of three days back for the disruption as a gesture of goodwill and to say sorry."
For pay as you go users who were affected, this will involve being offered an extra ten per cent on the first top up they make in September, with the credit to be added to their device automatically.
The network is also offering all its customers a £10 voucher to spend online or via the O2 Priority Moments app that will be redeemable throughout September.
Customers of Tesco Mobile and Giffgaff, which share O2's network and were also affected by last week's outage, will also be entitled to compensation measures.
Did you know you can use an ATM to add phone credit to your O2 pay as you go phone?