O2 has has made Ombudsman Services its third-party alternative dispute resolution (ADR) provider until at least 2022.
The partnership will see Ombudsman independently handle and investigate unresolved complaints made by O2 customers.
Ombudsman Services is one of two Ofcom-approved ADR providers in the communications sector. It also works with BT, EE, Plusnet and Three.
Ombudsman’s director of relationships Jodi Hamilton said: “We believe this agreement is good news for O2, its customers and Ombudsman Services.
“We work very closely at every level with O2 to drive the right behaviours and give the company the best possible chance of retaining customers who have a complaint.
“Using our data and insights, we take a pro-active approach with our business partners in order to make them aware of any trends we spot in the complaints we’re seeing about them.
“We also hold regular workshops for providers on new regulations and legislation affecting the communications sector.”
O2’s director of customer service Mark Gait added: “We are pleased to be continuing our relationship with Ombudsman Services.
“As a company that prides itself on delivering excellent customer service, we want our customers to have access to high-quality independent redress when there are disputes that can’t be resolved.
“We take complaints seriously and are always keen to make further improvements to our complaint handling and customer service more broadly.”
Ombudsman also extended its partnerships with the Internet Services Providers’ Association and the Internet Telephony Services Providers’ Association for a further three years.