Your phone company may start blocking robocalls by default.

On Wednesday, the FCC announced that it would propose new rules that, if adopted, would let phone companies prevent unwanted robocalls from reaching consumers’ phones via an opt-out process. Meaning, someone would have to ask the phone company to let all the bad calls through.

Because people may not always take the time to opt into certain call-filtering programs offered by phone companies, sweeping customers into blocking, like an email spam filter, could make a difference and provide relief to the nonstop barrage of robocalls.

The FCC said that the rule would provide a safe harbor for phone companies if they block calls they think are spam, letting them off the hook if that blocking were to otherwise pose a legal violation. According to the FCC, phone companies up until now have been concerned that blocking robocalls may be illegal.

“If this decision is adopted, I strongly encourage carriers to begin providing these services by default—for free—to their current and future customers,” said FCC Chair Ajit Pai in a press release.

First Orion, a company that provides anti-robocall services to the telecom industry, told Yahoo Finance that it recently surveyed mobile consumers and found that 84% would be inclined to choose a carrier that automatically blocked scam calls.

Right now, carriers are allowed to block calls if they are obviously spam, like some IRS numbers, which are incoming-only, and numbers that carriers haven’t assigned to people yet.

USTelecom, a large industry group representing phone companies like Verizon (Yahoo Finance’s parent) and AT&T, which also organizes a robocall tracking operation, supported the proposal, calling it “big and bold.”

Of course, identifying robocalls is another matter altogether. Currently, the industry is developing a caller ID authentication system called STIR/SHAKEN that should roll out over the next year. A number of companies have successfully exchanged calls with authentication. The idea behind opt-out blocking would be that phone companies would have leeway going forward to block calls it thinks are scams. When STIR/SHAKEN is broadly implemented, phone companies would only have to examine a basket of calls that can’t be verified — a smaller task.

Concerns exist, however, that some of these smaller companies — or larger, but poorer companies — may not have the money to implement and offer this technology to their customers, potentially leaving them hung out to dry if they try to call a company that has adopted STIR/SHAKEN.