AT&T will begin refunding 2.7 million customers for billed items they hadn’t agreed to including ringtones, wallpapers and text message subscriptions, the Federal Trade Commission confirmed.

The regulator announced in 2014 that a total of $88 million would be refunded to consumers for charges made for a range of services provided by third party suppliers Tatto and Acquinity.

Following a lengthy period of collating and verifying complaints, AT&T will credit current and former customers within the next 75 days.

According to the FTC’s complaint, AT&T placed unauthorised charges on bills for items including love tips, horoscopes and fact alerts in a technique called mobile cramming. Although some of this money was passed on to the third party providers, the FTC claims AT&T kept 35 per cent of the fees.

The operator changed its billing systems following the initial investigation.

FTC chairwoman Edith Ramirez said: “AT&T received a high volume of complaints related to mobile cramming prior to the FTC and other federal and state agencies stepping in on consumers’ behalf. I am pleased that consumers are now being refunded their money and that AT&T has changed its mobile billing practices.”