The Basics: What Are 4G and 5G?

4G and 5G are generations of mobile network technology. 4G has been the standard since around 2012, delivering reliable mobile broadband across most of the UK. 5G is the newer generation, rolling out since 2019, offering significantly faster speeds and lower latency.

For businesses, both can serve as primary or backup broadband connections using a router with a SIM card — no phone line required.

Speed Comparison

This is where 5G really shines:

• 4G typical speeds: 20-50Mbps download, 5-15Mbps upload
• 4G peak speeds: Up to 100Mbps in ideal conditions
• 5G typical speeds: 100-300Mbps download, 20-50Mbps upload
• 5G peak speeds: Up to 1Gbps+ in ideal conditions

To put that in context, 4G speeds are comparable to standard fibre broadband (FTTC). 5G speeds rival or exceed full fibre (FTTP) connections. For a small office of 5-10 people, even 4G provides enough bandwidth for VoIP calls, video conferencing, and general internet use.

Latency: Why It Matters for Business

Latency is the delay between sending and receiving data. Lower is better, especially for:

• VoIP phone calls — high latency causes delays and echo
• Video conferencing — lag makes meetings frustrating
• Cloud applications — everything feels sluggish with high latency
• Card payments — slow processing frustrates customers

4G latency is typically 30-50ms — acceptable for most business use. 5G latency drops to 10-20ms, which is comparable to fibre broadband and excellent for real-time applications.

Coverage: The Deciding Factor

This is where 4G still wins decisively in 2026:

• 4G coverage: Available across 99%+ of the UK population. Good coverage across most of Northern Ireland including rural areas
• 5G coverage: Available in Belfast city centre and some urban areas. Limited or no coverage in rural Northern Ireland

If you're in central Belfast, 5G is likely available and worth considering. If you're anywhere else in Northern Ireland, 4G is your reliable option. Use multi-network SIMs to get the best coverage regardless of location.

Cost Comparison

• 4G router: £100-300
• 5G router: £300-700
• 4G data SIM: £15-30/month for unlimited data
• 5G data SIM: £25-40/month for unlimited data

5G costs more for both hardware and data plans, though the gap is narrowing. For businesses where speed is critical and 5G coverage is available, the premium is worth it. For backup connectivity or basic business use, 4G offers excellent value.

Which Should Your Business Choose?

Choose 4G If:

• You're outside major urban areas (most of Northern Ireland)
• You need a cost-effective backup internet connection
• Your bandwidth needs are moderate (up to 10-15 users)
• Budget is a primary concern
• You need connectivity for temporary or remote sites

Choose 5G If:

• You're in Belfast or another area with confirmed 5G coverage
• You need speeds comparable to fibre broadband
• You're replacing fibre broadband entirely with mobile
• Low latency is critical for your applications
• You have bandwidth-heavy needs (large file transfers, multiple video calls)

Future-Proofing Your Business

5G coverage is expanding rapidly. If you're investing in a new business router today, it's worth considering a 5G-capable device even if you're currently on 4G. When 5G reaches your area, you'll automatically benefit from faster speeds without changing hardware.