iPhone dual SIM support seems to be a pain for all major carriers in the United States. Although it offered support for this feature at launch, AT&T had to give up after finding that the iPhone Visual Voicemail feature doesn’t work correctly when the handset’s lines are both active. Find out more about dual SIM card phones by Verizon below.

However, AT&T promises it will start to offer dual SIM support once Apple fixes the issue via a software update.

In an internal Verizon memo obtained by 9to5Mac, the company told employees it intends to have dual SIM activations for eSIM and physical SIMs ready to go by early December:

Currently, the iPhone does not support high-speed Verizon service when used in a dual SIM configuration, dropping down to the 2G CDMA network rather than LTE. This was especially problematic in certain geographies where Verizon has switched to offering LTE-only coverage.

As a result of these limitations, Verizon said it would not be activating service on any eSIM nor officially supporting Dual SIM activations.

At the launch last month, Verizon said they believed the software limitations would be resolved quickly with Apple’s cooperation. This latest memo indicates that it will stick to its promise and deliver eSIM and Dual SIM to iPhone XS and iPhone XR customers before the end of the year.

Note that the phones only support one eSIM and one physical SIM card slot outside of China, meaning that at least one of the lines will need to run through the eSIM slot.

• READ MORE: Countries & carriers which supports eSIM

In the case of Apple’s iPhones mentioned above, the second SIM is actually an eSIM that can be rewritten when you change your carrier. The eSIM is also very easy to handle by the carriers, which can add or remove data plans very quickly.

As VentureBeat noted, few U.S. customers use dual SIM configurations, though it is more common in Asia and Europe, where many people use two SIM cards to toggle between work and phone lines and national or international carriers. Lack of support for dual SIMs was considered a barrier to expanding market shares in some regions, and VentureBeat reported earlier this year that dual SIM support had been under consideration as a China-exclusive feature. dual sim card phones verizon