Boost4U G150 Review: Best Call Booster Under £100 (UK Tested 2025)
The Boost4U G150 is the best call-focused mobile signal booster under £100 in the UK, delivering 65 dB of gain on Band 8 (900 MHz) to cover 150 m² for O2, Vodafone, giffgaff and Sky Mobile users, lifting indoor signal from 0–1 bars to a full 4–5 bars in real-world testing, all for £85.00 with a 365-day money-back guarantee.
After four weeks of testing across three UK locations — a rural stone cottage, a city-centre basement flat and a suburban semi-detached house — the G150 consistently improved call success rates from as low as 35% to 98% or higher. This review covers everything: unboxing, installation, performance benchmarks, comparison with alternatives, and whether it is worth your money in 2025.
Who Is This Review For?
This review is for anyone in the UK who experiences dropped calls, poor voice quality or "No Service" indoors on O2, Vodafone, giffgaff, Sky Mobile, Tesco Mobile, Lebara, Lycamobile or VOXI, and who wants a low-cost, Ofcom-compliant solution without paying for an engineer or a £300+ branded booster.
Boost4U G150 — At a Glance
| Specification | Detail |
|---|---|
| Model | G150 / MBG150gb |
| Price | £85.00 (was £115.00, save 26%) |
| Frequency Band | Band 8 — 900 MHz (GSM / UMTS) |
| Supported Standards | 2G GSM, 3G UMTS (voice calls & SMS) |
| Max Gain | 65 dB |
| Max Output Power | 20 dBm EIRP |
| Coverage Area | Up to 150 m² (1,614 sq ft) |
| Noise Figure | ≤ 5 dB |
| Power Consumption | ≤ 10 W |
| Dimensions | 160 × 110 × 25 mm |
| Weight | ~450 g |
| Ofcom Status | Licence-exempt |
| Return Policy | 365-day money-back |
| UK Shipping | Free (10–15 business days) |
Unboxing — What's in the Box
The G150 arrives in a compact cardboard box with everything needed for installation. The booster unit itself is small — 160 × 110 × 25 mm — about the size of a paperback book, with a matte black plastic casing and three LED status indicators on the front (power, uplink, downlink).
| Item | Notes |
|---|---|
| G150 Booster Unit | Band 8 900 MHz amplifier, LED indicators |
| Outdoor Omni Antenna | 5 dBi, wall/pole mount, N-type connector |
| Indoor Panel Antenna | 5 dBi, wall/ceiling mount, N-type connector |
| Coaxial Cable | 10 m, 5D-FB low-loss, N-type both ends |
| Power Adapter | UK 3-pin, AC 100–240 V |
| Mounting Kit | Screws, wall plugs, cable ties |
| User Manual | English, step-by-step with diagrams |
The build quality is solid for the price. The antennas feel durable, the cable is properly shielded, and the connectors are standard N-type — meaning you can easily upgrade to longer or lower-loss cable if needed.
Installation — Step by Step
Step 1: Find the Best Outdoor Signal (5 minutes)
Before drilling anything, walk around your property's exterior with your phone. Open the Settings → About Phone → Network (or use the free Network Cell Info app) and note the signal strength in dBm at each corner. The goal is to find the spot with the strongest (least negative) reading. In our Devon test, the back of the cottage facing the nearest O2 mast showed -85 dBm, while the front showed -102 dBm — a 17 dB difference that significantly impacts booster performance.
Step 2: Mount the Outdoor Antenna (10 minutes)
Mount the omni-directional outdoor antenna at your chosen spot, ideally 2–3 metres above ground level on an exterior wall or pole. The omni design means it does not need precise pointing — it receives signal from all directions. Use the included screws and wall plugs, or a pole mount if available.
Step 3: Run the Cable (5 minutes)
Run the 10 m coaxial cable from the outdoor antenna through a window, vent or drilled hole to the indoor booster location. Avoid sharp bends (minimum bend radius 5× cable diameter) and keep cable away from power cables to prevent interference.
Step 4: Connect and Power Up (2 minutes)
Connect the outdoor antenna cable to the "BS" (Base Station) port on the booster. Connect the indoor panel antenna to the "MS" (Mobile Station) port. Plug in the power adapter. The LEDs will flash during calibration (about 30 seconds) then go solid green when ready.
Step 5: Test and Adjust (5 minutes)
Walk around the coverage area with your phone. Signal should improve immediately. If certain rooms are still weak, try repositioning the indoor antenna or increasing the outdoor antenna height.
Total installation time: 20–25 minutes with basic tools (drill, screwdriver, spanner).
Performance Test Results
Test Location 1: Rural Stone Cottage (Devon)
| Measurement | Before G150 | After G150 | Improvement |
|---|---|---|---|
| Signal Strength (dBm) | -112 dBm (0 bars) | -78 dBm (4 bars) | +34 dB |
| Call Success Rate (20 calls) | 7/20 (35%) | 20/20 (100%) | +65% |
| Average Call Quality (1–5) | 1.8 | 4.7 | +2.9 |
| Dropped Calls | 13/20 | 0/20 | -100% |
| SMS Delivery Time | 15–45 seconds | Instant | — |
Test Location 2: City Basement Flat (Manchester)
| Measurement | Before G150 | After G150 | Improvement |
|---|---|---|---|
| Signal Strength (dBm) | -101 dBm (1 bar) | -72 dBm (5 bars) | +29 dB |
| Call Success Rate (20 calls) | 12/20 (60%) | 20/20 (100%) | +40% |
| Average Call Quality (1–5) | 2.5 | 4.9 | +2.4 |
| Dropped Calls | 8/20 | 0/20 | -100% |
Test Location 3: Suburban Semi (Reading)
| Measurement | Before G150 | After G150 | Improvement |
|---|---|---|---|
| Signal Strength (dBm) | -95 dBm (2 bars) | -68 dBm (5 bars) | +27 dB |
| Call Success Rate (20 calls) | 16/20 (80%) | 20/20 (100%) | +20% |
| Ground Floor Coverage | 2 rooms weak | All rooms 4–5 bars | Full |
| First Floor Coverage | 1 bar | 3–4 bars | Good |
Pros and Cons — Honest Assessment
What We Loved
- Price: At £85.00, the G150 is genuinely affordable. Most comparable boosters cost £150–300.
- Performance: 65 dB gain delivered real improvements in all three test locations, with gains of 27–34 dB.
- Coverage: 150 m² is enough for the vast majority of UK flats and small houses.
- Easy install: 20 minutes with basic tools. The manual is clear and well-illustrated.
- Network support: Works with 8+ UK networks on O2/Vodafone infrastructure.
- 365-day returns: Unmatched in this price category. Most competitors offer 30 days.
- Low running cost: ≤10 W consumption means ~£10–15 per year in electricity.
- Ofcom compliant: No licence required, no risk of fines.
What Could Be Better
- Voice-only: The G150 does not boost 4G data. If you need internet, look at the C100.
- O2/Vodafone only: EE and Three users are out of luck. This is a Band 8 limitation, not a design flaw.
- 10 m cable: May be too short for larger properties or tricky installations. Upgrades are available.
- Outdoor antenna visibility: The omni antenna is visible on the exterior wall. Some renters may face restrictions.
- No app or monitoring: Unlike premium boosters, there is no smartphone app for signal monitoring or adjustment.
- LED indicators basic: Three LEDs show power/link status but not signal strength in dBm.
Boost4U G150 vs Alternatives
| Feature | Boost4U G150 | Boost4U G100 | Boost4U C100 | Uncertified eBay Booster |
|---|---|---|---|---|
| Price | £85.00 | £75.00 | £109.99 | £30–50 |
| Band | Band 8 (900 MHz) | Band 8 (900 MHz) | Band 20 (800 MHz) 4G | Variable / unknown |
| Coverage | 150 m² | 100 m² | 300 m² | Claimed 200–500 m² |
| Gain | 65 dB | 60 dB | 70 dB | Unknown (often fake) |
| Type | Voice (2G/3G) | Voice (2G/3G) | 4G LTE + VoLTE | Variable |
| Ofcom Compliant | Yes | Yes | Yes | No (illegal) |
| UK Support | Yes (lifetime) | Yes (lifetime) | Yes (lifetime) | No |
| Return Policy | 365 days | 365 days | 365 days | 30 days (if any) |
| UK Shipping | Free | Free | Free | Often from China |
| Risk Level | None | None | None | High (fine, interference) |
G150 vs G100 — Which Should You Choose?
The G100 is £10 cheaper but offers 50 m² less coverage and 5 dB less gain. If your home is under 100 m² (studio flat, single room), the G100 is fine. For anything larger — or if you want the extra gain margin for weaker outdoor signals — the G150 is worth the extra £10. In our testing, the G150's 65 dB gain made a noticeable difference in the weakest-signal location (Devon), where the G100 struggled to reach upstairs rooms.
G150 vs C100 — Data vs Voice
The C100 is a 4G LTE booster that costs £24.99 more but adds data support and 300 m² coverage. If you primarily need faster mobile internet and only secondary need for calls, the C100 is the better choice. If calls are your main problem and you already have decent WiFi or broadband, the G150 saves you money while solving the exact issue.
G150 vs Uncertified eBay Boosters
Uncertified boosters from eBay or Amazon marketplace may seem cheap at £30–50, but they are illegal to operate in the UK. They often cause interference to mobile networks, can result in a £5,000 fine, and rarely deliver the advertised gain. The G150's £85 price includes compliance, support and a 365-day guarantee — making it far better value in real terms.
Real User Experiences
We analysed 50+ verified customer reviews of the G150 across Trustpilot, Google Reviews and the Boost4U website. The consensus is overwhelmingly positive:
- 92% of reviewers reported improved call quality after installation
- 87% said installation took under 30 minutes
- 78% rated the value for money as "excellent"
- Common praise: "stopped my dropped calls", "easy to install", "worth every penny"
- Common complaints: "cable too short for my house", "wish it did 4G too", "outdoor antenna is visible"
Who Should Buy the G150?
- O2, Vodafone, giffgaff or Sky Mobile users with poor indoor call quality
- Homes or small offices up to 150 m²
- People on a budget who want an Ofcom-compliant solution
- Rural properties with strong outdoor signal but poor indoor penetration
- Basement flats and garden offices
- Anyone who wants to try a booster risk-free with 365-day returns
Who Should NOT Buy the G150?
- EE or Three network users (different frequency bands)
- People who need 4G/5G data boosting
- Properties over 150 m² (consider the C100 instead)
- Locations with zero outdoor signal (booster cannot create signal)
- Those who cannot mount an outdoor antenna (rented flats with restrictions)
Final Verdict
The Boost4U G150 earns our recommendation as the best call signal booster under £100 in the UK for 2025. It delivers on every promise: 65 dB of real gain, 150 m² of coverage, compatibility with all O2/Vodafone-family networks, and a price that makes it accessible to almost everyone. The 365-day money-back guarantee removes any risk, and the free UK shipping means the £85.00 price is the total cost.
For O2 and Vodafone users fed up with dropped calls, the G150 is the most cost-effective, compliant and reliable solution available. It is not the fanciest booster on the market, but it does exactly what it claims — and does it well.
Rating: 4.7 / 5 — Deducted 0.3 for voice-only limitation and fixed 10 m cable.
Buy the Boost4U G150 — £85.00 with free UK shipping →
Understanding dBm — The Science of Signal Strength
Mobile signal strength is measured in dBm (decibel-milliwatts), a logarithmic scale where more negative numbers mean weaker signal. Understanding dBm is essential for diagnosing signal problems and evaluating booster performance.
The dBm Scale Explained
| dBm Range | Quality | Bar Count (Typical) | Call Reliability |
|---|---|---|---|
| -50 to -65 | Excellent | 5 bars | Perfect, no drops |
| -65 to -75 | Very Good | 4–5 bars | Very reliable |
| -75 to -85 | Good | 3–4 bars | Reliable, rare drops |
| -85 to -95 | Fair | 2–3 bars | Occasional drops |
| -95 to -105 | Poor | 1–2 bars | Frequent drops |
| -105 to -120 | Very Poor | 0–1 bar | Most calls fail |
Because dBm is logarithmic, a 10 dB increase represents a 10× increase in signal power. The G150's 65 dB gain means it amplifies signal power by over 3 million times — enough to transform a -110 dBm (0 bar) signal into -45 dBm (5 bars) in ideal conditions. In practice, cable loss and antenna efficiency reduce the net gain to 27–34 dB, which is still enough to add 3–4 bars of signal.
How to Measure Your Signal in dBm
Android: Settings → About Phone → Network → Signal Strength. Or install the free "Network Cell Info Lite" app for real-time readings and mast location data.
iPhone: Dial *3001#12345#* to enter field test mode. The signal strength appears in the top-left corner. iOS 14+ may require you to tap the signal bars to toggle between bars and dBm.
Take readings at multiple locations and at different times of day (signal can vary with network congestion). The outdoor reading is the most important — it determines whether a booster will work.
Booster Technology Deep Dive
How Bidirectional Amplification Works
A mobile signal booster is not just a one-way amplifier — it operates in both directions simultaneously. The downlink path amplifies signal from the mast to your phone, while the uplink path amplifies signal from your phone back to the mast. Both paths must be balanced for reliable calls.
The G150 uses separate amplifiers for uplink (890–915 MHz) and downlink (935–960 MHz), with duplex filters to prevent the two paths from interfering with each other. This full-duplex design is what allows you to talk and listen at the same time without clipping or echo.
Automatic Gain Control (AGC)
AGC is a critical feature that prevents the booster from over-amplifying and causing oscillation (a high-pitched feedback loop similar to a microphone too close to a speaker). The G150's AGC continuously monitors signal levels and adjusts gain in real-time, reducing output by up to 20 dB if oscillation is detected. This is one of the key features that distinguishes compliant boosters from illegal grey-market units, which often lack AGC and cause network interference.
Oscillation Prevention
Oscillation occurs when the indoor antenna's amplified signal leaks back to the outdoor antenna, creating a feedback loop. The G150 prevents this through three mechanisms: AGC (detects and reduces gain), antenna separation requirement (minimum 5 m between indoor and outdoor antennas), and the directional characteristics of the panel antenna (which radiates primarily forward, not backward toward the outdoor antenna).
Cable Loss and Why It Matters
Coaxial cable loses signal at a rate determined by its quality and the frequency. At 900 MHz, the included 5D-FB cable loses approximately 0.4 dB per metre, meaning the 10 m cable introduces about 4 dB of loss. This is factored into the G150's 65 dB gain specification. If you need a longer cable run (e.g. for a two-storey house), upgrading to 7D-FB or LMR400 cable reduces loss to 0.2 dB/m, preserving more of the booster's gain for actual coverage.
Maintenance and Long-Term Care
The G150 requires minimal maintenance, but a few simple steps will ensure years of reliable performance. The booster unit has no moving parts and is designed for continuous 24/7 operation. However, the outdoor antenna is exposed to the elements and should be inspected annually.
Annual Maintenance Checklist
- Check outdoor antenna: Inspect for corrosion, loose mounting, or damage from storms. Tighten mounting bolts if necessary.
- Inspect cable connections: Check N-type connectors for signs of water ingress or corrosion. Apply dielectric grease if needed.
- Clean antenna: Wipe the outdoor antenna with a damp cloth to remove dirt, bird droppings or debris that can affect performance.
- Verify LED status: Ensure all three LEDs on the booster unit show solid green. A flashing red LED indicates oscillation or a connection issue.
- Test signal: Re-measure signal strength in dBm to confirm performance has not degraded over time.
- Check cable routing: Ensure cables have not been damaged by animals, gardening equipment or building work.
Common Wear and Tear
The most common failure point over time is the outdoor antenna cable connector, which can corrode if not properly sealed. Boost4U includes weather-sealed connectors with the G150, but if you notice signal degradation after several years, replacing the cable (a £10–15 part) is usually the fix. The booster unit itself should last 5–10 years or more with proper ventilation.
Frequently Asked Questions
Is the Boost4U G150 any good?
Yes. In independent testing across three UK locations, the G150 improved signal strength by 27–34 dB and achieved 100% call success rates where previously rates were as low as 35%. It represents excellent value at £85.00.
Does the G150 work with giffgaff?
Yes. giffgaff uses O2's network infrastructure, including the 900 MHz Band 8 frequency that the G150 amplifies. giffgaff calls and SMS will be boosted.
Can the G150 boost 4G internet?
No. The G150 is a voice-only booster for 2G GSM and 3G UMTS on 900 MHz. It does not improve 4G LTE or 5G data speeds. For 4G data, consider the Boost4U C100.
How long does the G150 last?
The G150 has no moving parts and is designed for 24/7 continuous operation. With proper installation, it should last 5–10 years or more. Boost4U provides lifetime technical support.
Does the G150 need WiFi?
No. The G150 operates independently of WiFi, amplifying the cellular signal directly from the nearest mast.
What is the difference between G150 and G100?
The G150 covers 150 m² with 65 dB gain, while the G100 covers 100 m² with 60 dB gain. The G150 is £10 more expensive but offers 50% more coverage and 5 dB more gain.
Is the G150 compatible with Sky Mobile?
Yes. Sky Mobile uses O2's network, so the G150 amplifies Sky Mobile calls and SMS on Band 8 900 MHz.
Can I use the G150 in a caravan or motorhome?
The G150 is designed for fixed indoor installation. For vehicles, consider the Boost4U CVC vehicle booster, which includes a magnetic-mount antenna and 12V power adapter.
What if I have thick stone walls?
Thick stone walls attenuate signal significantly, but the G150's 65 dB gain is designed to overcome this. In our stone cottage test, it improved signal by 34 dB. Ensure the outdoor antenna is mounted on the exterior wall facing the mast.
How do I return the G150 if it doesn't work?
Contact Boost4U customer support within 365 days of purchase to initiate a return. The product must be in resellable condition with all original packaging. Refunds are processed within 5–7 business days of receipt.
