The One Number Comcast Stock Investors Should Watch

The wireless phone service stands out at Comcast (CMCSA), and it may be what buyers of the stock are betting on. While Comcast is widely viewed as a cable company, wireless is where it is adding customers. Yet the stock has lost 23% over the past twelve months, while the S&P 500 returned 17.3%. That divergence presents a contradiction. So, how big has Comcast’s wireless business become?

Comcast Added A Record Number Of Wireless Lines

Comcast added a net 448,000 wireless lines in the second quarter of 2026. Management called the performance its best quarter on record, leaving the company with 10.2 million lines in total. This footprint represents just a fraction of the available market. Management noted those lines are only 7% of the wireless lines it could sell in the areas its network serves. Home internet went the other way. Comcast lost 167,000 broadband subscribers in the same quarter. The core business is shrinking while wireless grows, yet some of the new lines are on pricier plans. Premium unlimited plans made up roughly 30% of new postpaid phone connections.

Comcast Is Earning Less From Each Broadband Customer

The primary concern surrounding Comcast is that revenue per broadband customer fell 3.8% in the second quarter. Management outlined several factors on its second-quarter call in July. The company did not raise broadband prices, and it has been moving customers to simpler plans with lower everyday prices. Comcast is also giving away wireless lines, a move that lowers revenue per broadband customer at first. Management plans to start charging for the free lines, but for most of them that transition is still ahead. Roughly half of Comcast’s new residential postpaid phone connections came from customers taking a free line. Management expects a significant majority of those customers to become paying ones. Free lines do nothing about rivals. Management said fiber continues to expand and fixed wireless remains aggressive. Comcast stock trades at 6.6 times earnings, against 21.9 for the S&P 500. That reflects the price of a shrinking cable company.

What Could Go Wrong With Comcast’s Free Lines?

The free lines will remain a cost if customers do not start paying for them. Management stated on its July call that the significant majority of customers coming off a free line were converting to paid as expected. Management said in July that more of those free offers would end in the second half of the year, which is now well underway. The third-quarter report will be the first real test. Shareholders are also receiving less back while they wait for the free lines to turn into paid ones. Comcast plans to separate into two companies. It paused share buybacks on July 1 and expects to keep them paused until the separation. Management said in July that it aims to complete the separation in about a year. Over the past twelve months, buybacks came to 7.6% of Comcast’s market value. That payout is now on hold. The share of Comcast’s new wireless lines that are paid is the number to watch in its third-quarter report.

Does This Mean You Should Act On CMCSA?

Our purpose is to inform you with unique data so you make the right investment decisions. That said, betting on a single stock is always risky, no matter which direction you choose.

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