Listed below is a selection of free public NTP time servers available in the UK. The list is by no means exhaustive and has not been tested by TimeTools.
TimeTools cannot be held responsible for the availability or operation of the time servers listed on this page. We list a selection of links hoping that you may find them useful.
Stratum 1 NTP Servers
| Hostname | IP Address | DNS | Location and Type |
| chronos.csr.net | 194.35.252.7 | Yes | Computing Systems Research Ltd. UKNTP V4 primary (Odetics GPS), Sun/Sparc Solaris 2.6 |
| ntp.my-inbox.co.uk | 81.168.77.149 | No | Falmouth, Cornwall, UK NTP V4.2.0 primary (MSF Radio Clock Receiver), Trustix Linux |
Stratum 2 NTP Time Servers
| Hostname |
IP Address | DNS | Location and Type |
| ntp1.npl.co.uk | 139.143.5.30 | Yes | Time & Frequency Services National Physical Laboratory |
| ntp2.npl.co.uk | 139.143.5.31 | Yes | Time & Frequency Services National Physical Laboratory |
| ntp1.ja.net | 193.62.22.74 | Yes | JANET, Harwell |
| ntp2.ja.net | 193.62.22.98 | Yes | JANET, Harwell |
| ntp.virginmedia.com | 62.253.170.208 | Yes | Virgin Media |
| ntp2.sandvika.net | 194.164.127.6 | No | Telehouse Europe, London E14 NTP V4 secondary Sun UltraSPARC Solaris 8 |
| ntp2d.mcc.ac.uk | 130.88.203.12 | Yes | University of Manchester, Manchester, England NTP secondary (S2), SGI/Irix |
| ntp2c.mcc.ac.uk | 130.88.200.4 | Yes | University of Manchester, Manchester, England NTP secondary (S2), PC/FreeBSD |
| ntp.exnet.com | 194.207.34.9 | Yes | ExNet Ltd, London, UK NTP secondary (stratum 2), Sun-4/Unix |
| ntp1.sandvika.net | 194.164.127.5 | No | Telehouse Europe, London E14 NTP V4 secondary Sun UltraSPARC Solaris 8 |
| ntp0.csx.cam.ac.uk | 131.111.8.171 | Yes | Cambridge University |
| ntp1.csx.cam.ac.uk | 131.111.8.28 | Yes | Cambridge University |
| ntp2.csx.cam.ac.uk | 131.111.8.189 | Yes | Cambridge University |
| ntp.cis.strath.ac.uk | Yes | University of Strathclyde, Glasgow, Scotland NTP V4 secondary |
|
| ntp0.sandvika.net | 194.164.127.4 | No | Telehouse Europe, London E14 NTP V4 secondary Sun UltraSPARC Solaris 8 |
| ntppub.le.ac.uk | IPv4: 143.210.16.201 IPv6: 2001:630:306:10::c9 |
Yes | University of Leicester, Leicester, England NTP V4, stratum 2, GNU/Linux |
If you wish to suggest a reference for consideration for inclusion on this page, please feel free to contact us.
The NTP Pool Project
The NTP pool project is a large virtual cluster of internet based network time servers. Pools of servers are located in many countries around the world. Clients can therefore synchronize to relatively local references, which reduces network latency and round-trip delays and provides a more robust source of time.
The pools are used by millions of systems around the world. Indeed, many standard Linux distributions and network appliances use the pool project servers as their default source of time.
The project is maintained and developed by Ask Bjørn Hansen and a group of contributors. Servers are volunteered to the pool. Access to pool project servers is available over the internet to time clients free of charge.
The United Kingdom Pool Zone
The UK pool zone is referenced by the following domain names:
0.uk.pool.ntp.org
1.uk.pool.ntp.org
2.uk.pool.ntp.org
3.uk.pool.ntp.org
The domain names point to a random set of UK based time servers that change every hour. By regularly changing sets, client load can be evenly distributed to prevent overloading of individual servers.
For more information.See:
https://www.pool.ntp.org/
http://www.pool.ntp.org/zone/uk
Best Practice
If your business or organisation is dependent on an accurate source of time, you should consider installing a local hardware clock referenced NTP server. Internet based time references are often maintained by volunteers and there is no guarantee of accuracy or availability. Additionally, NTP authentication and security mechanisms cannot be used in conjunction with internet based servers. Therefore their use may leave your systems open to abuse.
TimeTools is a UK-based manufacturer of NTP servers and precision timing equipment. Based on GPS and LF radio technology, our products provide a reliable, accurate and traceable source of time for your network. If synchronized time is important to your organisation, please consider one of our hardware network time server appliances.
Related Information
We can also provide more information on Stratum 1 and 2 Internet based time references available in Australia, Germany (Deutschland), France (Francais) and Netherlands (Nederland).