- Optimum’s wireless customers have been running on the company’s own mobile core
- But now, they will obtain access to T-Mobile’s 5G SA core as well
- This will provide them with more options on devices and better international roaming
The cable operator Optimum has offered its customers a wireless service since 2019, but today Optimum says its service will improve with the capabilities of T-Mobile’s 5G standalone (SA) core.
For a little background, Optimum originally launched its mobile service as “Altice Mobile” in 2019, using Sprint’s wireless network. But in 2020, the underlying wireless network switched to T-Mobile after T-Mobile bought Sprint. In 2021, the service was officially renamed to Optimum Mobile, and in 2022, Optimum extended its multi-year mobile virtual network operator (MVNO) agreement with T-Mobile.
According to Luciano Ramos, Optimum’s chief product and technology officer, Optimum’s wireless service has run on its own, in-house-built mobile core network.
But today, Optimum says it has expanded its agreement with T-Mobile to allow Optimum customers access on T-Mobile’s 5G SA core.
“By doing this, we get access to [T-Mobile’s] core as well,” said Ramos. “T-Mobile has developed a lot of services on their standalone core. So, we want to get access to some of the services that they have developed on their core, rather than having to build it ourselves.”
This will give Optimum customers the ability to use their mobile service with a broader portfolio of smartphones, wearables, tablets and other connected devices.
Ramos said, “The benefits of the agreement don't really start to materialize until early in the next year. There is some work we have to do to upgrade a few platforms. But early next year, you'll see us coming up with new launches and improved offerings to our customers”
With its new expanded agreement with T-Mobile, Optimum will have access to two mobile cores — its own in-house core and T-Mobile’s 5G SA core. “We do believe most of our customers will end up in the T-Mobile standalone core at the end because they do have a wider portfolio of devices,” said Luciano. “We believe customers will choose devices that will put them on that side.”
Optimum will assign accounts to the best core based on the products and services that a customer chooses.
As Optimum migrates customers to the new core, it will also get access to different frequencies on the T-Mobile network that will give customers more speed and coverage.
The choice of core will also affect customer’s international roaming. This is an area where T-Mobile shines.
Luciano said Optimum offers international roaming via its partners. But he said, “T-Mobile, given their reach and their size, they have a bigger set of partners. There might be countries where we only have one partner, right? T-Mobile might have two or three in a particular country. So, it gives more opportunity for the phone to choose the best carrier for roaming.”
Optimum is primarily a broadband provider, which also offers the option to bundle the mobile service. Luciano said the new deal with T-Mobile gives Optimum “the opportunity to rethink our packages around how we want to evolve our product set now that we have these capabilities.”
Fierce asked if other cable operators such as Comcast and Charter built their own mobile cores, and Luciano said, “No, they run on the Verizon network, 100% on Verizon's core.”
As of Q2 2026, Optimum has reached 724,000 mobile lines.
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