Zen Internet Fibre Speed Test Guide (2026)

Zen Internet customers should receive average download speeds of 100Mbps, 500Mbps, or 900Mbps depending on their Full Fibre plan, with upload speeds that are among the best on both the Openreach and CityFibre networks. Zen Internet is a Which? Recommended Provider with an 84% customer satisfaction score (2026) and offers a speed guarantee: if your broadband falls below the minimum guaranteed speed and Zen cannot fix it, you can exit your contract for free. Zen also acquired FibreHop's consumer broadband base in September 2025.

Expected Zen Internet Speeds by Package

Zen Internet offers Full Fibre packages on both Openreach and CityFibre networks, with speeds varying slightly by network. Full Fibre 100 delivers around 100Mbps download with approximately 18Mbps upload on Openreach, or fully symmetric 100Mbps on CityFibre, from approximately £30–35 per month. Full Fibre 500 provides 500Mbps download and around 70Mbps upload on Openreach, or symmetrical 500Mbps on CityFibre, from around £36–42 per month. Full Fibre 900 averages 900Mbps download and around 100Mbps upload on Openreach, or 900Mbps symmetrical on CityFibre. Zen also offers a Full Fibre Max plan (available on CityFibre in select areas) reaching 1,600–2,300Mbps, from £56–65 per month. In February 2026, Zen discounted its Openreach FTTP prices significantly, with the 500Mbps plan available at £39 per month. Zen acquired FibreHop's customer base in September 2025, expanding its reach across CityFibre areas. Like Cuckoo, Zen is a B Corp certified provider and does not impose mid-contract price rises — a notable differentiator. All plans include a free static IP address and free router.

How to Run a Speed Test on Zen Internet Broadband

For an accurate Zen Internet speed test, connect your device directly to the Zen-supplied router using an ethernet cable. Zen provides a dedicated speed check tool at zen.co.uk/help-support/check-your-speed, which tests against Zen's own network servers and can give more relevant results than generic third-party testing services. On the Full Fibre 500 and 900 plans, confirm your ethernet port is Gigabit-capable — a 100Mbps port will artificially limit results to approximately 94Mbps. On the Max plan (up to 2.3Gbps), a 2.5Gbps ethernet adapter is needed for full throughput. Pause all active downloads, cloud syncs, and streaming on every household device before testing. Run the test at least three times and average the results. If you are on a CityFibre plan, your upload speed should closely match your download — a significant gap indicates a configuration issue. Zen maintains a minimum guaranteed speed for every plan and will investigate and remedy any sustained shortfall.

Understanding Your Zen Internet Speed Test Results

Zen's speed test displays four critical metrics. Download speed (Mbps) is the headline figure, governing streaming quality (4K Netflix requires ~25Mbps), web browsing, and file downloads. Upload speed is where Zen's CityFibre plans stand out — symmetric 500Mbps or 900Mbps upload is far superior to Openreach's 75–110Mbps uploads at the same speed tier. Latency (ping) on Zen Full Fibre should be around 5–10ms to UK servers via ethernet — user reports typically range 5–18ms — which is excellent for gaming and video conferencing. Jitter should be under 3ms on a well-maintained full fibre connection. Zen's speed guarantee is a practical commitment: if your speed falls below the minimum stated at sign-up, Zen must fix it within 30 days or let you leave penalty-free. This goes further than the basic Ofcom Voluntary Code minimum. Compared with BT and Plusnet on the same Openreach infrastructure, Zen consistently scores higher for customer satisfaction and complaint resolution.

How to Improve Your Zen Internet Speeds

Zen includes a quality router with all plans — typically a BT-compatible FTTP router for Openreach plans, or a comparable device for CityFibre. Router placement in a central location, away from microwaves, cordless phones, and baby monitors, maximises Wi-Fi coverage. Use the 5GHz band for close-range devices and 2.4GHz where range is prioritised over speed. For larger homes, a mesh Wi-Fi system connected via ethernet to the Zen router will provide the most consistent whole-home coverage. Ethernet connections from the router to gaming consoles, smart TVs, and desktop computers eliminate Wi-Fi overhead and consistently achieve speeds close to the full line rate. Zen also includes a free static IP address with all plans, which is useful for remote workers who need VPN or self-hosted services — though this does not affect speed performance. Zen's 100% UK-based support team is available to run remote line diagnostics if speeds remain below the guaranteed minimum after basic troubleshooting. Restarting the router monthly and keeping firmware up to date resolves many intermittent issues.

Compare Broadband Deals at Your Address

Zen Internet is one of the highest-rated broadband providers in the UK by customer satisfaction. Zen Full Fibre packages start from around £30 per month on 18-month contracts. Use CompareFibre to check whether Zen is available on Openreach or CityFibre at your address.

Frequently Asked Questions

What is Zen Internet's speed guarantee?

Zen Internet provides a minimum guaranteed speed for every Full Fibre plan. If your connection speed falls below this minimum and Zen cannot fix it, you are entitled to exit your contract without a penalty charge. This goes beyond the basic Ofcom Voluntary Code and reflects Zen's confidence in its network performance.

Does Zen use Openreach or CityFibre?

Zen Internet uses both. Openreach FTTP is available to approximately 99% of UK postcodes via Zen, while CityFibre coverage is available in 40+ UK cities and towns. CityFibre plans offer symmetric upload speeds, which match the download speed. Openreach plans have higher download than upload. The postcode checker at zen.co.uk confirms which network is available at your address.

What happened to FibreHop customers — are they now on Zen?

Yes. Zen Internet acquired FibreHop's consumer broadband customer base in September 2025. FibreHop was a CityFibre-based ISP serving 68+ UK towns. Former FibreHop customers have been migrated to Zen Internet, where they continue to receive service on the CityFibre network. Zen is considered a high-quality upgrade in terms of customer service and support compared with FibreHop.

Related Guides

Zen Internet Fibre Deals · CityFibre Speed Test · BT Fibre Speed Test · Broadband Speed Guide · Zen Internet Network Migration Guide

Methodology

This guide is based on publicly available data from Ofcom, provider websites, and independent sources including ISPreview.co.uk, Thinkbroadband, and Point Topic. Pricing, speeds, and availability were verified in April 2026 and are subject to change. CompareFibre is editorially independent — providers do not pay for placement or influence our recommendations.