NEW YORK — Sony’s streaming TV service is expanding nationwide, giving TV lovers a new, potentially cheaper way to get cable channels.

PlayStation Vue will start at $30 a month in the new regions. That’s $10 cheaper than current packages, but it won’t include over-the-air channels. Vue’s seven older markets — big cities including New York City and San Francisco — won’t have access to the new, cheaper deal.

More people are bypassing traditional TV services in light of extensive online offerings from the likes of Netflix and HBO Now. To reach them, cable and satellite TV companies are launching Internet-based services.

Vue’s new plans could make it a more significant challenger to traditional TV services. But Craig Moffett, a MoffettNathanson analyst, says “nobody really knows how big the opportunity will be.”