4G LTE - 250m2 (EE/O2/Vodafone/Three) Mobile Signal Booster
✓ Compatible with multiple users and devices
✓ Complete kit: all parts included
✓ Simpler Install and Maintenance
Enhance your mobile experience with our selection of signal boosters for EE, O2, Vodafone, and Three networks, designed to improve indoor coverage across the UK.
Frequently Bought Together
Boost4U C250 High-Power 4G LTE Mobile Signal Booster
Up to 250 m² indoor coverage · 72 dB max gain · 3.5 dB ultra-low noise figure · 25 simultaneous users. Engineered for large detached homes, offices, cafés and rural UK premises on EE, O2, Vodafone & Three.
The Boost4U C250 is a high-power Band 20 (800 MHz FDD LTE) mobile signal booster engineered to deliver up to 250 m² (2,691 sq ft) of reliable 4G indoor coverage with 72 dB maximum gain and a 3.5 dB ultra-low noise figure. Supporting all four UK networks — EE, O2, Vodafone and Three — plus 20+ MVNOs, the C250 handles up to 25 simultaneous users with Ofcom-approved AGC automatic gain control, requires no operating licence, and installs in 20–25 minutes as a DIY solution. Priced at £199.99, it sits as Boost4U's premium large-premises model, and is covered by a 365-day money-back guarantee and lifetime UK technical support.
C250 Full Technical Specifications
| Parameter | Value |
|---|---|
| Product Name | Boost4U C250 High-Power 4G LTE Mobile Signal Booster |
| Model / SKU | C250 / MBC250gb / B4U-C250-UK |
| Price | £199.99 GBP |
| Frequency Band | Band 20 (FDD LTE) |
| Uplink Frequency | 832 – 862 MHz |
| Downlink Frequency | 791 – 821 MHz |
| Maximum Gain (Total) | Up to 72 dB |
| Uplink Gain | ≥ 50 dB |
| Downlink Gain | ≥ 55 dB |
| Max Output Power (EIRP) | 20 dBm |
| Indoor Coverage Area | Up to 250 m² (2,691 sq ft) |
| Noise Figure | 3.5 dB (ultra-low) |
| Power Consumption | ≤ 15 W |
| Power Supply | AC 100–240 V, 50/60 Hz, UK 3-pin plug |
| Simultaneous Users | Up to 25 devices |
| VoLTE Support | Yes (HD voice over LTE) |
| AGC (Auto Gain Control) | Yes — advanced digital AGC |
| Indoor Antenna | Panel antenna, 8 dBi, wall/ceiling mount, N-type |
| Outdoor Antenna | Omni-directional, 8 dBi, wall/pole mount, N-type |
| Standard Cabling | 10 m low-loss 5D-FB outdoor cable + 5 m indoor cable, N-type both ends |
| Cable Upgrade Options | 20 m / 30 m / 40 m / 50 m |
| Upgradable Accessories | High-gain Yagi directional antenna, 18 kA lightning surge protector |
| Dimensions | 200 × 130 × 30 mm |
| Weight | Approx. 650 g |
| Certification | Ofcom licence-exempt (built-in AGC + power limiting) |
| Installation Time | 20–25 minutes, DIY, no engineer required |
| Warranty | 365-day money-back guarantee + lifetime technical support |
| Delivery | Free UK shipping · 10–15 working days · 1–2 day handling |
Pros & Cons — Honest C250 Review
Pros
- Industry-leading 250 m² coverage — comfortably covers large detached homes, offices and cafés where smaller boosters fall short.
- 72 dB max gain with 3.5 dB noise figure — clean, distortion-free 4G signal even at the edge of coverage; the low noise figure preserves call clarity and data speeds.
- Supports 25 simultaneous users — ideal for small businesses, co-working spaces and multi-bedroom family homes.
- All four UK networks + 20+ MVNOs — works with EE, O2, Vodafone, Three, giffgaff, Sky Mobile, Tesco Mobile, VOXI, SMARTY, Lebara and more.
- Ofcom licence-exempt — built-in AGC and EIRP power limiting mean no Ofcom paperwork or application needed.
- DIY install in 20–25 minutes — no engineer call-out cost; panel + omni antennas and N-type connectors are tool-free friendly.
- VoLTE-ready with advanced AGC — supports HD voice calls over 4G and automatically adjusts gain to avoid oscillation or over-driving the donor signal.
- 365-day refund + lifetime support — lowest-risk purchase in the premium booster segment.
Cons
- 4G-only (Band 20 / 800 MHz) — does not boost 3G calls; you must be on a VoLTE-enabled SIM and handset for voice. Falls back to no service on older 2G-only phones.
- Premium price at £199.99 — a significant step up from Boost4U's smaller 100 m² and 200 m² models; overkill for a small flat or single room.
- Requires at least 1–2 bars of outdoor 4G signal — if your exterior has zero usable Band 20 signal, no booster can create it from nothing.
- Outdoor antenna needs exterior wall or pole mounting — may be unsuitable for listed buildings, conservation areas, or tenants without landlord permission.
- Not suitable above 250 m² — open-plan warehouses, barn conversions or shops over two storeys will need multiple units or a dedicated DAS design.
- Standard 10 m cable may need upgrading — if your donor antenna mounts far from the indoor unit, you'll need the 20 m / 30 m / 40 m / 50 m upgrade cable.
- 15 W power draw is higher than smaller models — running 24/7 adds roughly £15–20/year on your electricity bill (small, but not zero).
How the C250 Works — Three-Step Signal Chain
Outdoor Donor Antenna
The 8 dBi omni-directional outdoor antenna captures weak Band 20 (800 MHz) 4G signal from the nearest mobile mast through your exterior wall or roof line.
C250 Amplifier Unit
The indoor unit amplifies the captured signal up to 72 dB using advanced AGC (Automatic Gain Control). The 3.5 dB ultra-low noise figure ensures the amplified signal stays clean — no static, no dropped calls, no data throttling.
Indoor Panel Antenna
The 8 dBi wall- or ceiling-mounted panel antenna rebroadcasts the boosted 4G signal across up to 250 m², serving up to 25 simultaneous phones, tablets and connected devices.
Why the 3.5 dB noise figure matters: a booster with a high noise figure amplifies the signal and the noise together, resulting in choppy VoLTE calls and slow data. At 3.5 dB, the C250 sits near the top of the consumer booster class, preserving SNR (signal-to-noise ratio) so your data throughput stays close to what you'd get standing next to the mast.
DIY Installation — 6 Steps in 20–25 Minutes
UK Carrier & MVNO Compatibility
| Network | Type | Band 20 / 800 MHz Support | VoLTE on C250 |
|---|---|---|---|
| EE | Main network | Yes | Yes |
| O2 | Main network | Yes | Yes |
| Vodafone | Main network | Yes | Yes |
| Three | Main network | Yes | Yes |
| BT Mobile | MVNO (EE) | Yes | Yes |
| Plusnet Mobile | MVNO (EE) | Yes | Yes |
| giffgaff | MVNO (O2) | Yes | Yes |
| Sky Mobile | MVNO (O2) | Yes | Yes |
| Tesco Mobile | MVNO (O2) | Yes | Yes |
| Lebara | MVNO (Vodafone) | Yes | Yes |
| VOXI | MVNO (Vodafone) | Yes | Yes |
| iD Mobile | MVNO (Three) | Yes | Yes |
| SMARTY | MVNO (Three) | Yes | Yes |
| Asda Mobile | MVNO (Vodafone) | Yes | Yes |
| Lycamobile | MVNO (O2) | Yes | Yes |
| Talkmobile | MVNO (Vodafone) | Yes | Yes |
| Virgin Mobile | MVNO | Yes | Yes |
The C250 amplifies Band 20 (800 MHz) signal for any SIM that roams on EE, O2, Vodafone or Three — that covers 20+ MVNOs in total. Only one frequency band is boosted; if your carrier's Band 20 signal is weak outdoors, the C250 will help. If Band 20 is already strong on your roof, the C200 or C100 may be sufficient.
What's in the Box
| Item | Specification | Quantity |
|---|---|---|
| C250 Booster Unit | 200 × 130 × 30 mm, 650 g, 72 dB gain | 1 |
| Outdoor Omni Antenna | 8 dBi, N-type, wall/pole mount | 1 |
| Indoor Panel Antenna | 8 dBi, N-type, wall/ceiling mount | 1 |
| Outdoor Low-Loss Cable | 10 m, 5D-FB, N-type both ends | 1 |
| Indoor Cable | 5 m, N-type both ends | 1 |
| UK Power Supply | AC 100–240 V, 50/60 Hz, UK 3-pin plug | 1 |
| Mounting Kit | Screws, wall plugs, pole bracket | 1 set |
| User Manual | Quick-start guide + full installation PDF | 1 |
Optional upgrades available at checkout: 20 m / 30 m / 40 m / 50 m extension cable, high-gain Yagi directional antenna, 18 kA lightning surge protector.
Best-Fit Applications for the C250
Large Detached Homes
200–250 m² family houses with thick stone walls, basements or multiple storeys where a single 50–100 m² booster leaves dead zones upstairs.
Small Offices
5–25 person offices needing reliable 4G for VoIP, video calls and mobile hotspots — the 25-simultaneous-user rating matches a typical team.
Cafés & Bistros
Hospitality venues where guests expect strong 4G on their phones — boosts signal across the seating area without relying on venue Wi-Fi.
Pubs & Bars
Cellar-level bars, stone-built pubs and rural inns with patchy EE/O2/Vodafone/Three — the 8 dBi omni donor pulls in distant mast signal.
C250 Frequently Asked Questions (UK)
Which UK networks does the Boost4U C250 support?
The C250 boosts Band 20 (800 MHz FDD LTE) signal for all four major UK networks — EE, O2, Vodafone and Three — plus 20+ MVNOs including BT Mobile, Plusnet, giffgaff, Sky Mobile, Tesco Mobile, Lebara, VOXI, iD Mobile, SMARTY, Asda Mobile, Lycamobile, Talkmobile and Virgin Mobile. If your SIM runs on one of the four main networks, the C250 will amplify its Band 20 signal.
How much faster will my 4G data speeds get?
The C250 doesn't add extra bandwidth — it improves the signal-to-noise ratio at the edge of coverage. In a typical weak-signal UK home, expect download speeds to climb from 1–5 Mbps to 20–50 Mbps and uploads from <1 Mbps to 5–15 Mbps, depending on your mast distance and outdoor signal level. The 3.5 dB noise figure is the key spec that preserves throughput instead of amplifying noise.
Will the C250 really cover 250 m²?
Yes — up to 250 m² (2,691 sq ft) under ideal conditions where the outdoor antenna captures a decent Band 20 donor signal. Real-world coverage depends on wall construction, floor layout and interference. Thick stone or solid concrete walls reduce the effective covered area; open-plan modern homes can exceed the rated area. If your premises are larger than 250 m², you'll need multiple C250 units or a custom DAS design.
Is it legal to use a mobile signal booster in the UK without a licence?
Yes — the C250 is Ofcom licence-exempt because it includes built-in AGC (Automatic Gain Control) and EIRP power limiting capped at 20 dBm, which Ofcom's regulations require for consumer boosters. You do not need to apply to Ofcom or notify your network operator. Boosters that lack AGC or exceed the power limit are illegal in the UK.
Can I install the C250 myself or do I need an engineer?
You can install it yourself in 20–25 minutes. The kit includes pre-terminated N-type cables, wall/pole mounting brackets and a step-by-step quick-start guide. The only tool required is a drill for the wall cable gland. No soldering, no configuration software, and no engineer call-out fee.
What if I have zero 4G signal outside my house?
The C250 cannot create signal from nothing — it amplifies an existing weak outdoor signal. If your outdoor antenna location shows 0 bars on your phone, the C250 won't help. In that case, first try relocating the outdoor antenna to the roofline or a taller pole; if there is still no Band 20 signal, you may need to explore satellite broadband or a different frequency band solution. The 365-day refund covers this scenario.
Does the C250 support VoLTE (HD voice calls over 4G)?
Yes — the C250 is fully VoLTE-ready. Because it boosts Band 20 LTE only, voice calls travel over 4G (VoLTE) rather than 3G. You need a VoLTE-compatible handset and a SIM on a carrier that supports VoLTE in your area (all four UK networks do). On older 2G/3G-only phones, the C250 will improve data but not voice calls.
How much does the C250 cost to run per year?
The C250 draws up to 15 W at the wall. At typical UK electricity rates, running it 24/7 costs approximately £15–20 per year. It is designed to be always-on — there is no need to switch it off — and the AGC automatically adjusts power draw based on live signal conditions.
I live in a listed building or rent — can I install the C250?
Installation requires drilling a small hole for the outdoor cable and mounting the omni antenna on an exterior wall or pole. In a listed building or conservation area, external antenna mounting may require planning permission — check with your local council. If you rent, we recommend getting written landlord permission before drilling. An alternative is to run the cable through an existing window or loft hatch without drilling.
What is the returns policy and warranty?
The C250 comes with a 365-day money-back guarantee — if it doesn't improve your signal within one year, return it by mail for a full refund (free return). You also get lifetime UK-based technical support by email and chat. The unit itself is built to CE/Ofcom standards and the power supply has UK 3-pin safety certification.
Learn More: C250 Buying Guides & Setup Resources
Best 250 m² High-Power 4G Signal Booster UK (2026) — C250 Review
A head-to-head comparison of high-gain boosters for large homes, with real-world coverage tests and cost-per-m² analysis.
Premium Mobile Signal Booster Under £200 UK — Is the C250 Worth It?
We compare the C250 at £199.99 against budget and mid-range options to show when paying for 72 dB gain actually pays back.
4G Signal Booster for Large Detached Houses — Floor-by-Floor Setup Guide
How to position the donor and panel antennas to eliminate dead zones across two storeys, basements and home offices.
4G Signal Booster for Small Offices & Businesses — UK Setup Guide
Why 25 simultaneous users matters for a 10-person team, and how to deploy the C250 for VoIP and video calling reliability.
Enhanced 4G/LTE Signal
Experience a significant boost in your 4G/LTE signal with our Mobile Signal Booster. Designed to enhance connectivity for EE, O2, Vodafone, and Three networks, it ensures you stay connected even in areas with weak signals.
Wide Coverage Area
Cover up to 250 square meters with reliable mobile signal. Perfect for homes, cafes, restaurants, and offices, this booster guarantees a strong connection throughout your space.
User-Friendly Installation
Our Mobile Signal Booster comes with a complete kit, making installation a breeze. With all necessary components included, you can set it up quickly and easily without professional help.
Supports Multiple Devices
Connect up to 25 devices simultaneously without compromising on signal strength. Whether it's for family, friends, or colleagues, everyone can enjoy seamless connectivity.
VoLTE Compatibility
Make crystal-clear voice calls using 4G Calling (VoLTE) technology. This booster not only enhances data speeds but also improves call quality, ensuring you never miss an important conversation.
Durable and Reliable
Built to last, our Mobile Signal Booster is designed for durability and consistent performance. Enjoy uninterrupted connectivity, rain or shine, with a device that stands the test of time.
3 Steps to Full Bars
1. Place the Outdoor Antenna
Mount the antenna where you get the best signal.
2. Connect the Booster Inside
Plug in the booster and connect to the antenna.
3. Enjoy Full Bars Everywhere
Clear calls, fast data, and no more dead zones.
4G LTE Mobile Signal Booster EE Signal Booster O2 Signal Booster Vodafone Signal Booster Three Signal Booster Indoor Coverage UK Mobile Booster
It boost 4G/LTE signal on 800MHz frequency, the frequency used in UK used by mobile networks to deliver their 4G mobile services. It can boost all networks on Three, EE, O2, Vodafone, BT, Asda, Virgin, giffgaff, Talkmobile, Lyca Mobile, Tesco, iD Mobile, Freedom Pop, Orange, Plusnet, Sky Mobile, Smarty Mobile, T-Mobile and The People's Operator for improving 4G/LTE signal. If your phones support 4G Calling (also called Voice over LTE or VoLTE) and your area 4G Calling is available, with the booster you can make clearer voice calls using 4G network. It is the best suitable for medium size, boost indoor signal areas up to 250 m2, perfect for home, cafes, restaurants, pubs, clubs and more.
Note: This booster improve EE 4G LTE signal only on Band 20 - 800MHz frequency, EE 4G LTE Band 3 - 1800MHz frequency boosters, can purchase our 1800MHz boosters.
Reliable 4G/LTE Data
Faster Uploads & Downloads
Reception Up to 250 sq.m.
Upgrade External Cables
If our standard package 10 meter external cable length is not enough to cover your area you have an upgrade option.
Upgrade External Aerial
Higher Gain Yagi Antenna - For better performance it's a must if indoor your phone with 1/2 signal bars. Or get this upgrade if outdoor best signal strength in the following range:2G (GSM) -76 to -90 dBm
3G (UMTS) -80 to -94 dBm
4G (LTE) -97 to -105 dBm
How to shown dBm reading on phone? Check Quick Start Guide
Upgrade Protector
Lightning Surge Protector - Designed to Protect your equipment from high amperage surges due to lightning strikes on aerials or masts in close proximity to the device. This unit is rated for 18KA of current surge and is very simple to install on any device.
Specification
| Application & Bands | [4G/LTE] (Band 20) |
| Country | United Kingdom |
| Boost All On | EE (4G) O2 (4G) Vodafone (4G) Three (4G) Asda (4G) BT (4G) Freedom Pop (4G) giffgaff (4G) iD Mobile (4G) Talkmobile (4G) Lyca Mobile (4G) Orange (4G) Plusnet Mobile (4G) Sky Mobile (4G) Smarty Mobile (4G) Tesco (4G) The People's Operator (4G) T-Mobile (4G) Virgin (4G) |
| Users Supporting | 25 Simultaneously |
| Band | Single Band 20 |
| Frequency | 800MHz |
| Gain(dB) | Uplink Gp≥50; Downlink Gp≥55 |
| Up-link | 832~862 MHz |
| Down-link | 791~821 MHz |
| Export Power(Po) | ≥10dBm |
| Power Adapter | Input: AC 100V~240V 50/60Hz; Output: DC 5V |
| What’s Included | 1 x Booster 1 x Outdoor Antenna 1 x Indoor Antenna 1 x UK Type Power Adapter 1 x 10 Meters Outdoor Cable 1 x 5 Meters Indoor Cable |
Custom your solution
Expandable coverage by adding indoor antenna if the outside signal is strong.
How It Works
1
The powerful antenna reaches out to access a voice and 3G, 4G, and LTE data signal, and delivers it to the booster
2
The booster receives the signal, amplifies it, and serves as a relay between your phone and the nearest cell tower.
3
Your devices get increased cell reception, and calls and data are fed through the booster back to the network.
Get stronger signal
Normal Cell Coverage
Dropped calls and slow data are generally caused by three things: distance from a cell tower, building materials in your home or office, or obstruction from tall objects such as trees, topography, and buildings.
Signal Coverage with our booster
Signal boosters increase cell signal by collecting signals with a powerful antenna, delivering those signals to the booster, amplifying the cell signals so your devices receive them, and delivering your device's boosted signals back to the cell tower.Installation
- Connect the indoor antenna to the MS port.
- Connect the outdoor antenna to the BS Port.
- Install the outdoor antenna and keep a minimum vertical distance of 10 meters from the indoor antenna.
- Point the outdoor antenna to the direction where you know there is possibly a higher signal strength from the base station.
- Power on the booster and check the signal strength.
- Adjust the outdoor antenna until you get the best signal strength.
IMPORTANT NOTE:
DO NOT POWER ON THE DEVICE UNTIL YOU HAVE COMPLETED THIS SETUP.
Read more about User Manual Documentation.
Application Scenarios
Home
Office
Garage
Metal Buildings
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Why You'll Love It
Powerful Signal Boost
Easy Installation
Networks Supported
Fast Speeds
Crystal Clear Calls
Wide Coverage Area
Award-Winning Signal Booster
2026 Winner
Smart Features, Made Simple
Easy Setup
Smart Technology
Energy Efficient
Reliable Performance
24/7 Support
Secure & Safe
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