US operators could soon have more leeway to fight spam calls, as the Federal Communications Commission (FCC) proposed new rules which would allow them to block such traffic by default.

Many operators already offer call blocking services on an opt-in basis, but the rule would allow them to provide automatic filtering with a consumer opt-out clause.

Under the proposal, such programmes would be allowed to operate “based on any reasonable analytics designed to identify unwanted calls” and either block a call altogether or dispose of them in other ways, for instance by sending them straight to voicemail. It would also give the green light for so-called white list filtering, allowing operators to block calls from numbers not on a consumer’s contact list.

The FCC noted many operators have held off creating such tools due to questions surrounding their legality under current rules. However, Chairman Ajit Pai said in a statement the move will “give voice service providers the legal certainty they need to block unwanted calls from the outset so that consumers never have to get them”.

While Pai called on operators to offer such call blocking services for free, the proposal contains no mandate that they do so.

Despite attempts to tackle the issue, spam calls continue to represent a significant nuisance for US consumers. Data from caller ID service Hiya showed there were 26.3 billion robocalls made to US mobile phones in 2018.

The FCC will vote on the proposal at a meeting on 6 June.