Usually, a 4G SIM can work in a 3G phone only if the carrier accepts the SIM and handset and a compatible 3G network is still operating where you use it. It will not make a 3G-only phone connect to 4G LTE: that requires LTE-capable radio hardware in the phone. After 3G service ends, a 3G-only handset cannot use that retired network.
Why a 4G SIM does not make a phone 4G
The SIM identifies or provisions your subscriber account; the phone’s radio hardware determines which mobile network technologies it can use. A 3G-only handset cannot communicate over LTE just because you insert a SIM marketed as 4G. It may still connect to a supported 3G network if that network remains available and the carrier permits the device and SIM. Xiaomi explains that a phone without 4G support cannot use 4G through a SIM card alone; the FCC distinguishes 3G and 4G LTE as separate technology categories in its mobile technology codes guidance.
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First check what “3G phone” means
Some phones sold during the 3G era also have LTE; others are strictly 3G-only. A family name or purchase date is not enough to tell. Look up the exact model number in the manufacturer’s specifications, then check that specific model with your carrier. LTE support alone may not be sufficient: the phone must support the carrier’s bands and configuration, and the carrier may require device approval. Rogers’ VoLTE guidance directs customers to verify exact-model compatibility.
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Will it still work after 3G shuts down?
A 3G-only phone cannot use a 3G network after that network is retired. Shutdown timing is specific to the carrier and location, so there is no single worldwide end date. In the United States, the FCC’s 2022 order recorded carrier-reported 3G retirements and schedules; it is historical U.S. context, not a schedule for every country. FCC 22-96. In Saskatchewan, SaskTel’s February 2026 notice scheduled its 3G/HSPA shutdown for October 1, 2027; check SaskTel’s current notice for updates.
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- Please note, this device does not support E-SIM; This 4G model is compatible with all GSM networks worldwide outside of the U.S. In the US, ONLY compatible with T-Mobile and their MVNO's (Metro and Standup). It will NOT work with other CDMA carriers, and it is also not compatible with their MVNO (Visible, Xfinity Mobile, US Mobile, Cricket Wireless, etc).
- Compatibility with certain third-party devices and accessibility accessories, including some hearing aids, may vary depending on manufacturer support, Bluetooth protocols, software compatibility, and regional firmware limitations. For additional hearing aid compatibility information, please refer to Samsung’s official support documentation.
- Camera: 50 MP, f/1.8, (wide), 1/2.76", 0.64µm, AF | 50 MP, f/1.8, (wide), 1/2.76", 0.64µm, AF | 2 MP, f/2.4, (macro). Battery: 5000 mAh, non-removable | A power adapter is NOT included.
LTE data does not guarantee calling: check VoLTE
VoLTE means voice calls over LTE. Once a carrier’s 3G network is gone, an LTE phone generally needs carrier-supported VoLTE for voice service. An LTE-capable phone can therefore handle LTE data yet fail to place ordinary calls if VoLTE is unsupported, disabled, or not accepted by the carrier. Rogers says, “If you have a 3G or 2G phone you will need to upgrade to an LTE or 5G phone that supports VoLTE.” Rogers’ VoLTE FAQs provide its device and service guidance. For Saskatchewan, SaskTel’s shutdown guidance lists a VoLTE-compatible LTE/5G device and an LTE/5G SIM among the requirements for service after its 3G/HSPA shutdown.
Check compatibility before relying on the phone or buying another
- Identify the exact handset. Find the model number in the phone’s settings, on its packaging, or on the device label; do not rely only on the product family name.
- Check the carrier’s current device compatibility. Ask whether that exact model is accepted, supports the carrier’s network bands, and can use a network still active in your location.
- Confirm voice support. If you need calls after 3G retirement, ask whether the exact model supports the carrier’s VoLTE implementation and is approved, enabled, and provisioned for it.
- Verify the SIM and account. Confirm that the SIM type and plan are supported in that handset. A SIM that fits physically does not establish network or account compatibility.
- Check roaming separately. Compatible LTE data does not guarantee voice or emergency calling abroad if the necessary roaming arrangement is unavailable. SaskTel notes this limitation in its 3G shutdown guidance.
If replacement is necessary, look for an LTE or 5G phone that supports your carrier’s VoLTE—not merely an “unlocked” model—and confirm its exact model number with the carrier before purchasing. A SIM adapter, replacement SIM, SIM cutter, or software change cannot add LTE radio hardware to a 3G-only phone.
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- Please note, this device does not support E-SIM; This 4G model is compatible with all GSM networks worldwide outside of the U.S. In the US, ONLY compatible with T-Mobile and their MVNO's (Metro and Standup). It will NOT work with Verizon, Spectrum, AT&T, Total Wireless, other CDMA carriers, it is also not compatible with their MVNO (Visible, Xfinity Mobile, US Mobile, Cricket Wireless, etc).
- Compatibility with certain third-party devices and accessibility accessories, including some hearing aids, may vary depending on manufacturer support, Bluetooth protocols, software compatibility, and regional firmware limitations. For additional hearing aid compatibility information, please refer to Samsung’s official support documentation.
- 4G LTE Bands: B1/B3/B5/B7/B8/B20/B28/B38/B40/B41
- Display: Super AMOLED, 90Hz, 800 nits (HBM) | 6.7 inches, 110.2 cm2 (~86.0% screen-to-body ratio) | 1080 x 2340 pixels, 19.5:9 ratio (~385 ppi density)
- Camera: 50 MP, f/1.8, (wide), 1/2.76", 0.64µm, AF | 50 MP, f/1.8, (wide), 1/2.76", 0.64µm, AF | 2 MP, f/2.4, (macro)
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- GSM Unlocked: Enjoy seamless connectivity with your preferred GSM carrier. Compatible with T-Mobile, Metro PCS, AT&T, Cricket, Mint Mobile and other GSM networks. SIM card not included. For network compatibility, please check with your carrier. Note: Not compatible with CDMA networks like Verizon (Visible, Spectrum Mobile, US Mobile, Total Wireless, Straight Talk Wireless)
- Boundless Views: Enjoy immersive viewing on the spacious 6.5” HD+ display. Whether you're watching videos, browsing, or gaming, every detail comes through with stunning clarity.
- Smooth Performance, All Day: Powered by an efficient octa-core processor, the G35 ensures smooth performance for your everyday tasks. Enjoy faster app launches, seamless multitasking, and reliable speed.
- Snap, Share, Repeat: The G35 features a dual rear camera setup for sharp, detailed shots, and a front-facing camera that’s perfect for selfies and video calls. Capture every moment with ease and clarity.
- Effortless Access: Keep your phone secure with A.I. Face ID technology. Instantly unlock your G35 with just a glance. It's fast, easy, and secure.
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- Blazing-fast Qualcomm performance. Get the speed you need for great entertainment with a Snapdragon 680 processor and 4GB**** of RAM.
- Fluid display + immersive stereo sound. Bring your entertainment to life with an ultrawide 6.5" 90Hz* HD+ display plus stereo speakers, Dolby Atmos, and Hi-Res Audio**.
- 50MP*** Quad Pixel camera. Capture sharper, more vibrant photos day or night with 4x the light sensitivity.
- 64GB**** built-in storage. Get plenty of room for photos, movies, songs, and apps—and add up to 1TB more with a microSD card*****.
- Unbelievable battery life. Work and play nonstop with a long-lasting 5000mAh battery.*****
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- Seamless Connectivity with Dual SIM Flexibility** – This 4G unlocked smartphone is designed to work flawlessly with T-Mobile LTE and Wi-Fi Calling networks. It's also compatible with popular virtual carriers like Metro by T-Mobile, Mint Mobile, Ultra Mobile, Tello, Boost Mobile, and more. For detailed compatibility with your carrier's Bring Your Own Device program, it's best to consult with them directly. Please note, this device is not compatible with AT&T, Cricket, or CDMA networks such as Verizon and Sprint. Nano SIM cards are sold separately.
- Experience Luxury on a Bigger Screen** – The expansive 6.79” HD+ display delivers stunning visuals with deep contrasts and vibrant colors, transforming every video, game, or photo into a visually compelling experience. Perfect for those who demand more from their screens.
- Massive Storage for All Your Essentials** – With a generous 128GB of internal storage and support for an additional 512GB via MicroSD (sold separately), you have more than enough space to store everything that matters – from photos and videos to documents and apps. Say goodbye to the frustration of running out of storage.
- Blazing Fast Performance for All Your Needs** – Powered by 6GB of RAM and a powerful Octa-Core processor, experience seamless multitasking and lightning-fast responsiveness. Enjoy gaming, streaming, and browsing with zero lag and crystal-clear calls wherever you go.
- Unleash Your Inner Photographer** – The 50MP AI camera system is engineered to capture life's most beautiful moments with breathtaking clarity and detail. From perfect selfies to stunning landscapes, every photo will look like a work of art.
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