5G New Radio (NR) uses two distinct frequency ranges with fundamentally different propagation characteristics: Sub-6 GHz (FR1) and millimeter wave (FR2, commonly called mmWave). Sub-6 GHz bands behave similarly to LTE — they travel long distances, penetrate walls, and form the backbone of broad 5G coverage. mmWave bands carry significantly more data per cell but cover only short distances and struggle with obstacles. Understanding which range your device and carrier use determines what 5G actually means in practice.
Key points covered in this article:
- How 3GPP defines FR1 and FR2, with the specific frequency ranges and band numbers assigned to each
- The physics behind the coverage-versus-throughput trade-off between Sub-6 GHz and mmWave
- Why indoor performance differs so sharply between the two ranges
- How NSA and SA network architecture affects which bands a device uses
- How to read a device spec sheet to identify supported 5G NR bands
- Global deployment patterns and what they mean for travellers
For the technical background on how 5G voice calls work on top of this radio layer, see VoLTE and VoNR Explained. For guidance on matching your device’s band support to a specific carrier before selecting a plan, see How to Choose a SIM Plan.
The 3GPP Framework: FR1 and FR2
3GPP — the international body that defines mobile network standards — divides 5G NR spectrum into two frequency ranges, defined in 3GPP TS 38.104.
FR1 (Frequency Range 1) covers 410 MHz to 7.125 GHz. This range is commonly called Sub-6 GHz, though the actual upper boundary is 7.125 GHz. FR1 encompasses low-band frequencies below 1 GHz (such as 600 MHz and 700 MHz), widely deployed mid-band frequencies around 2.5–3.7 GHz, and upper mid-band frequencies up to 7.125 GHz. The majority of commercial 5G deployments worldwide use FR1 bands.
FR2 (Frequency Range 2) covers 24.25 GHz to 52.6 GHz as specified in 3GPP Release 15. Signals in this range have wavelengths measured in millimetres — hence the common name “millimeter wave” or “mmWave.” FR2 enables very high spectral efficiency per cell but with a propagation range measured in hundreds of metres under ideal outdoor conditions.
The distinction between FR1 and FR2 is not marketing terminology; it is a defined technical boundary in the 3GPP specification that determines which hardware components a device or base station uses. An FR1 radio and an FR2 radio require different antenna designs, RF front-end components, and beamforming approaches.
5G NR Band Numbering: FR1 and FR2
5G NR bands are identified by the prefix “n” followed by a number. FR1 bands are defined in 3GPP TS 38.101-1; FR2 bands in 3GPP TS 38.101-2. Many FR1 NR bands reuse the same frequencies as LTE bands with the same or similar numbers, which simplifies spectrum refarming — the process of reassigning existing spectrum from LTE to 5G NR.
Sub-6 GHz (FR1) bands
The following table lists the most widely deployed FR1 NR bands globally.
| Band | Frequency Range | Duplex | Common Deployment Context |
|---|---|---|---|
| n1 | 1920–2170 MHz | FDD | Europe, Asia — legacy 3G refarmed |
| n3 | 1710–2170 MHz | FDD | Europe, Asia — high-density coverage |
| n5 | 824–894 MHz | FDD | Americas, Asia — low-band coverage |
| n28 | 703–803 MHz | FDD | Asia-Pacific, Europe — sub-1 GHz coverage |
| n41 | 2496–2690 MHz | TDD | USA (T-Mobile), China — primary mid-band |
| n66 | 1710–2200 MHz | FDD | Americas |
| n71 | 617–698 MHz | FDD | USA (T-Mobile) — low-band coverage |
| n77 | 3300–4200 MHz | TDD | Europe, Asia, Americas — primary mid-band |
| n78 | 3300–3800 MHz | TDD | Europe, Asia — primary mid-band |
| n79 | 4400–5000 MHz | TDD | Japan (NTT Docomo, au, SoftBank, Rakuten) |
Bands n77 and n78 are the most broadly deployed 5G NR bands in Europe, many Asian markets, and parts of the Americas. They occupy the 3.5 GHz range and offer a practical balance: cell radii of several hundred metres to a few kilometres depending on terrain, and substantially higher throughput than LTE on equivalent spectrum.
Band n79 (4.4–5.0 GHz) is used primarily in Japan, where the Ministry of Internal Affairs and Communications assigned this range to domestic carriers. Devices sold specifically for the Japanese market include n79 support; many international handsets do not.
mmWave (FR2) bands
All FR2 bands use TDD (Time Division Duplex), because designing separate FDD uplink and downlink at these frequencies would require excessively large frequency separations.
| Band | Frequency Range | Key Market |
|---|---|---|
| n257 | 26.5–29.5 GHz | USA (Verizon 28 GHz), Japan, South Korea |
| n258 | 24.25–27.5 GHz | Europe (26 GHz), South Korea |
| n259 | 39.5–43.5 GHz | Japan, USA |
| n260 | 37.0–40.0 GHz | USA |
| n261 | 27.5–28.35 GHz | USA (Verizon, AT&T, T-Mobile) |
In the United States, the FCC licensed mmWave spectrum in three major blocks: the 24 GHz band (close to n258), the 28 GHz band (n261), and the 39 GHz band (n260). US carriers were the first to deploy mmWave commercially at scale, beginning in 2019. Other mmWave deployments include Japan (n257 at 28 GHz, by NTT Docomo, au, SoftBank, and Rakuten) and South Korea (n257 and n258).
mmWave deployments outside these markets remain limited as of 2026. The European 26 GHz band (corresponding closely to n258) has seen licensing activity but limited large-scale commercial rollout compared to mid-band 5G.
Why Coverage and Speed Trade Off
The difference in performance between FR1 and FR2 follows directly from the physics of radio wave propagation.
Wavelength and diffraction. Radio waves diffract (bend) around obstacles roughly in proportion to their wavelength relative to the obstacle size. At 700 MHz (FR1, ~43 cm wavelength), signals diffract around buildings, foliage, and terrain features to a meaningful degree. At 28 GHz (FR2, ~11 mm wavelength), diffraction is negligible. A building in the signal path results in a deep shadow zone with no service.
Free-space path loss. Path loss increases with both distance and frequency. The Friis transmission equation shows that for a given antenna gain, doubling the frequency doubles the path loss (adds approximately 6 dB). Moving from 700 MHz to 28 GHz represents a 40× increase in frequency, which translates to roughly 32 dB additional free-space path loss at the same distance. This forces mmWave base stations to operate at shorter ranges to maintain a usable signal level.
Atmospheric and material absorption. At 28 GHz and above, oxygen and water vapour in the atmosphere absorb radio energy at a measurable rate. Standard glass reduces a 28 GHz signal depending on composition: plain clear glass typically 3–10 dB, while coated or low-emissivity glass (common in modern buildings) can reach 20–40 dB. Concrete walls can attenuate a 28 GHz signal by 40 dB or more. FR1 signals pass through these same obstacles with much lower loss — standard glass reduces a 3.5 GHz signal by roughly 3–5 dB.
Available bandwidth. mmWave bands offer much wider channel widths. 3GPP allows channel bandwidths up to 400 MHz per component carrier in FR2 (versus a maximum of 100 MHz per component carrier in FR1 for Sub-6 GHz). This wider bandwidth is the primary mechanism behind mmWave’s higher peak throughput.
The net result: FR1 mid-band (n77/n78) cells cover urban areas and reach indoors with moderate penetration loss. FR2 cells are deployed outdoors in dense pedestrian environments — shopping districts, stadiums, transport terminals — where a direct line of sight to the antenna is likely and cell range of a few hundred metres is acceptable.
The table below summarises the key differences:
| Property | FR1 Sub-6 GHz | FR2 mmWave |
|---|---|---|
| Typical cell range | Hundreds of metres to several km | Up to ~200–300 m outdoors |
| Building penetration | Moderate (low-band: good; mid-band: usable near windows) | Poor to none without indoor cells |
| Max channel bandwidth (3GPP) | 100 MHz per component carrier | 400 MHz per component carrier |
| Beamforming requirement | Helpful for capacity; not mandatory | Mandatory for link budget |
| Primary use case | Coverage layer, mass-market 5G | High-density outdoor hotspots |
Indoor Performance
Indoor behaviour is where the FR1-vs-FR2 distinction is most consequential for everyday users.
A Sub-6 GHz 5G NR signal on mid-band (3.5 GHz) entering a modern office building typically loses 10–20 dB through exterior walls, leaving a usable indoor signal for devices near windows or on outer floors. Low-band 5G (below 1 GHz, such as n28 or n71) penetrates to interior floors and basements with less loss, similar to how 700 MHz LTE performs in building interiors today.
mmWave signals entering a building are effectively blocked by standard construction materials. Any mmWave 5G service inside a building requires an indoor small cell or distributed antenna system (DAS) with mmWave radios placed within the interior. Such indoor deployments exist in some venues — large US arenas and airports, for instance — but they are infrastructure-intensive and not the typical residential or office scenario.
For a subscriber choosing a SIM plan with 5G access, this means: if the carrier’s 5G relies entirely on mmWave, indoor service in most buildings will default to LTE. If the carrier has deployed FR1 mid-band 5G, indoor coverage on upper floors or near windows is realistic.
Low-band FR1 (n28, n71) offers the best indoor reach of any 5G tier, but the narrowest available channel bandwidth of the three sub-ranges.
NSA vs SA Architecture and Band Selection
5G NR can be deployed in two architectures defined by 3GPP:
NSA (Non-Standalone), standardised in 3GPP Release 15 Option 3, uses an LTE anchor for the control plane (signalling) while adding a 5G NR layer for user-plane data throughput. In NSA, the device must first connect to LTE; the 5G NR layer is then added as a secondary cell. This is called EN-DC (E-UTRAN New Radio Dual Connectivity). Because NSA relies on an LTE anchor, the LTE bands the device supports directly affect whether 5G can activate — a device that lacks the carrier’s LTE anchor band will not use 5G even if it supports the NR band.
SA (Standalone), standardised in 3GPP Release 15 with the 5G Core (5GC), allows a device to connect entirely over 5G NR without an LTE anchor. SA enables features that NSA cannot support, including 5G-native network slicing, lower latency (because signalling also runs on 5G NR), and VoNR (Voice over New Radio). SA requires the carrier to have deployed the full 5G Core network, which involves more infrastructure investment than NSA.
For devices checking band support: on an NSA network, the device’s spec sheet should list both the NR bands and the LTE bands that serve as anchors. On an SA network, only the NR bands matter for 5G connection. Most carriers specify which architecture they use on their network information pages.
How to Check Device Band Support
Manufacturer spec sheets are the definitive source for band information. The process is the same for any device:
Step 1: Find the exact model number. Manufacturers often sell regional variants of the same commercial model under identical marketing names but with different internal model numbers and different band support. On Android, the model number is under Settings → About Phone → Model Number. On iPhone, it is under Settings → General → About → Model Number. The box and SIM tray also carry the model number.
Step 2: Look up the spec sheet on the manufacturer’s website. Search for the model number on the manufacturer’s support or specifications page. For iPhones, Apple’s technical specifications page lists supported bands per region variant. For Android devices, the manufacturer’s product page or a direct search for “[model number] specifications” typically returns the official spec sheet.
Step 3: Identify the 5G NR band list. The spec sheet will list Sub-6 GHz NR bands (FR1) separately from mmWave NR bands (FR2). FR1 bands appear in the format n1, n3, n28, n77, n78, etc. FR2 bands appear as n257, n258, n260, n261. A device without any FR2 entries does not support mmWave.
Step 4: Cross-reference with the carrier’s published band plan. Major carriers publish their 5G frequency band allocations on their network or technology pages. Match the carrier’s bands against the device’s supported list. If the carrier uses n78 and the device supports n78, 5G should connect on that network.
Regional variant mismatch is the most common source of unexpected non-connectivity. A phone purchased in Japan and used in Europe may lack n77 or n78, which are the primary 5G bands for European carriers. A US-market iPhone supports a different set of FR2 mmWave bands than a European-market iPhone because the FCC licensed different mmWave blocks than European national regulators.
For how carrier-locking or country restrictions can additionally block certain bands or features, see SIM Lock and SIM-Free Explained. For how roaming on a foreign network affects which bands your device can use, see International Roaming: How It Works.
5G Deployment Patterns Globally
Understanding how carriers have deployed 5G frequencies helps set realistic expectations when travelling or switching plans.
South Korea and Japan deployed Sub-6 GHz 5G (primarily n77/n78/n79) at scale beginning in 2019. South Korea also deployed 28 GHz mmWave (n257) in limited urban areas. Japan’s major carriers (NTT Docomo, au, SoftBank, Rakuten) all hold n79 licenses and have deployed it alongside n77/n78.
China deployed 5G on n41 (2.6 GHz, TDD) and n78 (3.5 GHz) extensively through China Mobile, China Unicom, and China Telecom. China’s scale of deployment makes it one of the largest 5G markets by subscriber count.
Europe primarily uses n78 (3.5 GHz) as the main 5G band, with n28 (700 MHz) as a low-band complement for coverage extension. mmWave deployment is limited; the 26 GHz range has been licensed in some countries but large-scale commercial service is not yet widespread.
United States is unusual in having significant mmWave deployments (n260, n261) alongside mid-band (n41, n77) and low-band (n71) 5G. Verizon launched 5G using 28 GHz (n261) and 39 GHz (n260) mmWave as its initial 5G offering. T-Mobile’s primary mid-band 5G uses n41 (2.5 GHz). AT&T uses n77 (3.5 GHz) mid-band alongside n14 (700 MHz) low-band.
For an international traveller, this means: a device with broad FR1 support (n1, n3, n28, n41, n71, n77, n78) will access 5G in most major markets. mmWave support is relevant primarily within the United States. If your device includes n79 and you travel to Japan, you may access 5G on bands unavailable in your home country — but only if the device is not SIM-locked or network-restricted.
For guidance on choosing a SIM that matches your travel destination and your device’s band support, SimFinder allows filtering by country and carrier to compare plan options. For advice on which type of carrier (MNO or MVNO) gives access to the underlying 5G bands, see What Is an MNO?.
Carrier Aggregation and Reading a Carrier’s Band Plan
NR Carrier Aggregation
Carriers can combine multiple NR component carriers — on the same band or on different bands — to increase effective throughput. This is called NR Carrier Aggregation (NR CA), defined in 3GPP Release 15 and expanded in later releases.
Common NR CA combinations include:
- Two FR1 carriers on the same band (intra-band CA), which uses wider total bandwidth within a single carrier’s spectrum block
- Two FR1 carriers on different bands (inter-band CA), such as n28 + n78, combining low-band coverage reach with mid-band throughput
- FR1 + FR2 (inter-band FR1-FR2 CA), combining Sub-6 GHz coverage with mmWave throughput where both are available
For NR CA to activate, the device, the base station, and the carrier’s network configuration must all support the specific CA combination. Not all devices that support both n28 and n78 will support inter-band CA between them; the combination must appear explicitly in the device’s supported CA combination list, which is typically in the detailed modem specification rather than the summary spec sheet.
The practical consumer implication: NR CA extends the performance ceiling of 5G connections but is not required for basic 5G access. A device that supports only one NR band per network will still connect to 5G; it will not benefit from CA-boosted throughput.
Where to find a carrier’s band plan
Carriers publish their frequency band assignments in several places:
- Official network pages: Most major carriers maintain a “Network Technology” or “Frequencies” section on their website listing 4G and 5G bands by region.
- National regulator databases: Spectrum licensing is a matter of public record. National telecom regulators (FCC in the US, Ofcom in the UK, BNetzA in Germany, MIC in Japan, etc.) publish spectrum assignment databases showing which operator holds which band in which geographic area.
- GSMA data: The GSMA maintains operator and network information that includes frequency band data.
- Third-party band databases: Sites that compile operator band information exist but vary in accuracy and currency; cross-check against official carrier or regulator sources for critical decisions.
When comparing SIM plans for a trip or a long-term switch, confirming that the carrier’s 5G bands match your device’s supported bands is the final step before committing. Even if two carriers both offer 5G service, one may use n78 (which your device supports) and the other n79 (which it does not), producing different real-world results from the same hardware.
FAQ
See the frontmatter for structured FAQ entries compatible with schema.org/FAQPage. Additional context follows.
What does “Sub-6 GHz” mean exactly? The term is a shorthand referring to the FR1 frequency range, which 3GPP defines as 410 MHz to 7.125 GHz in TS 38.104. Industry usage of “Sub-6 GHz” conventionally means the bands below 6 GHz used for 5G NR — primarily the 600 MHz–5 GHz range. The 7.125 GHz upper boundary (sometimes called “upper-mid-band” or “FR1-High”) was added in later 3GPP releases and is used in some markets including the United States.
Can a device lose 5G and fall back to LTE? Yes. This is by design. When a device moves out of 5G NR coverage — because the cell edge is reached, because the device enters a location with poor 5G signal, or because the network temporarily offloads traffic — it falls back to LTE. On NSA networks, this happens silently as the 5G secondary cell is dropped. The device icon changes from “5G” to “4G” or “LTE.” LTE service continues normally during fallback.
Is 5G NR backward compatible with LTE? 5G NR and LTE use different physical layer standards (different waveforms, numerologies, and frame structures). A 5G NR base station cannot serve an LTE-only device on the NR carrier, and vice versa. However, in NSA deployments, the same tower can run both LTE and NR radios; an LTE-only device uses the LTE radio while a 5G NR device uses both. In standalone NR, only NR-capable devices benefit.
What is upper mid-band (FR1-High) 5G? 3GPP Release 17 and later releases expanded FR1 upward to 7.125 GHz (sometimes referenced as the “7 GHz band”). The US FCC has auctioned spectrum in the 3.45 GHz range (near n77) and is examining 7 GHz range spectrum. Japan’s MIC has designated the 4.9 GHz range (n79) and explores upper mid-band allocations. These upper FR1 bands offer greater available bandwidth than the congested 3.5 GHz range while retaining better propagation than FR2.
Related Guides
- VoLTE and VoNR Explained — How voice calls use IMS over the 4G and 5G NR radio layers described in this article
- What Is an MNO? — How licensed spectrum is held by MNOs and passed through to MVNOs
- International Roaming: How It Works — How visited-network band support affects which 5G bands you can use abroad
- SIM Lock and SIM-Free Explained — How carrier locking can restrict access to bands your device hardware supports
- How to Choose a SIM Plan — A practical decision framework that includes matching device bands to carrier networks