eSIMs vs physical SIM cards
A SIM card is a chip inside your phone that stores information and connects you to a wireless network. SIM cards used to all be physical pieces of plastic with circuit boards, but most modern phones support electronic SIM cards (eSIMs) that are stored digitally. Some newer smartphones no longer include a physical SIM card tray at all.
Why you should use an eSIM
Both physical SIM cards and eSIMs will get you connected to our networks. We highly recommend eSIM if your device supports it. eSIMs unlock the full potential of our network switching and multi-network features. You can also get activated instantly without waiting for a SIM card to ship.
Comparing physical SIM to eSIM
| eSIM | Physical SIM | |
|---|---|---|
| Form factor | Digital chip built into the phone | Removable plastic chip inserted into a SIM tray |
| Activation speed | Instant, no waiting for delivery | Standard shipping ships in 4–6 business days |
| Risk of loss or damage | Cannot be lost or physically damaged | Can be lost, bent, or damaged |
| Compatible devices | iPhone XS (2018) and later; Samsung Galaxy S20 (2020) and later, Galaxy Z Fold and Z Flip series; Any phones with eSIM support | iPhone 13 (2021) and earlier; Any other phones with physical SIM card trays |
| Moving your line to another device | Move your eSIM to another device digitally in our app | Take out the SIM card and put it in the new device |
Using a physical SIM card on US Mobile
We recommend eSIM for all of the reasons above. If you decide to use a physical SIM card, make sure your phone still has a SIM card tray. For example, iPhone 14 (2022) and later no longer have physical SIM card trays.
When you purchase a plan, you can choose to have a SIM card shipped to you. If you need more, you can also order individual SIM cards from our website or order a US Mobile Starter Kit. The Starter Kit offers both Warp and Dark Star SIM cards in one package at no extra cost.
SIM cards are network specific so make sure you're getting the right one for the network you want to use: Dark Star, Warp, or Light Speed.
SIM card sizes
All US Mobile SIM cards are 3-in-1, which means you can break every SIM card into any of the three common SIM card sizes.
- Mini SIM card (Standard SIM): 15 x 25mm. Used in 2011 phones and older, like the iPhone 3. Most smartphones no longer use this size
- Micro SIM card: 12 x 15mm. Commonly used by phones manufactured between 2012-2013, like the iPhone 4. Not widely used anymore
- Nano SIM card: 8.8 x 12.3mm. The smallest and most recent SIM size. If you have a newer generation phone, like iPhone 5 and above, you'll use the nano-sized SIM
Using existing SIM cards
You can't use a SIM card from another carrier or one of our SIM cards for a different network. You need a US Mobile Light Speed SIM (white) to get onto our Light Speed network, a Warp SIM (black) for the Warp network, and a Dark Star SIM (red) for the Dark Star network.
If you're returning to US Mobile and would like to re-use your old SIM card (Warp only), get in touch with our customer support.
Switching to an eSIM
You can switch to an eSIM by going into the app, selecting the line you'd like to switch, and selecting Transfer to eSIM in Line Settings.
For more info, read our guide on moving SIMs from one device to another.
Shipping time estimates
- Standard shipping: You can expect to receive your order within 4-6 business days
- Standard shipping: You can expect to receive your order within 2 business days
- Overnight shipping: You can expect to receive your order the next business day
Bulk SIM orders
Discounted bulk pricing automatically applies on orders for more than 9 SIM cards (not Starter Kits).
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