Almost every route out of Britain runs along the seabed — cut enough and your mail doesn't fail with a bang, it fails quietly: sign-in stops working within a day, security certificates expire over the weeks after.
Ordinary day. Mail moves between British sites over the domestic network, and crosses the water over subsea cable to every market Britain trades with. The twelve mainland sites in the middle are the only part of this picture that does not rest on the seabed.
Dart Mail is a standby mailbox that sits behind your everyday email, and takes over if something happens.
Your Microsoft or Google setup stays exactly as it is.
No migration, no retraining, nothing for your staff to learn — until the day it matters.
Not just the seabed
Send mail between two British desks and the message itself might never cross open water. Everything that lets it move usually does — the sign-in check, the load balancer, the spam filter, the certificate that proves the connection is real. Take any one of those away and delivery stalls, even between two people down the corridor.
If any one of those overseas stops cannot be reached, the mail queues — even though the sender and the recipient are inside Britain.The full eight-part breakdown of what holds and what fails is in The risk.
Sovereign by construction
Email needs four things to work: an address, a directory that finds it, computers that hold the messages, and an ID card that proves the whole thing is really yours. Most British organisations have all four sitting abroad. Ours are here, and we will tell you exactly where.
The bit after the @ sign — the name people write to.
One shared British .uk domain for every customer, not one registered per account — fewer registrations and DNS zones that could each become a point of failure abroad. Personal members get name@dartmail.uk; business and corporate get name.yourco@dartmail.uk.
The internet's phone book. It turns your address into the location of the machine holding your mail.
Ours is answered by machines standing in Britain. Nobody has to telephone abroad to look you up.
Your messages live on real machines in real buildings somewhere.
Ours are in named British datacentres we will tell you the address of — not "Europe", not "the cloud". Actual buildings, on British soil.
The certificate behind the padlock in your browser. It proves a mail server really belongs to you, and it expires every few weeks.
Renewing one normally means asking an office abroad. Ours are renewed here, so they keep working on the day that office cannot be reached.
The short version
Here's our thoughts and concerns in more detailreoi.
Licensing
This is insurance pricing for a mailbox nobody uses until they have to. A limited number of founder licences are open now, and the half-price rate holds for as long as you keep the account — it does not spring back at renewal.
To keep this a genuine standby rather than a parallel inbox, live traffic is capped at 10 messages a month during peacetime — enough to prove sign-in, delivery and certificates all still work. That cap lifts automatically to full capacity the moment failover activates.
* Larger mailbox storage can be purchased for any plan.
What you are buying today. Dart Mail is in pre-launch and the service is not yet live. Reserving buys one year's licence at half price and fixes that rate for as long as you keep the account. Your licence year does not start until we launch — you are not paying for months of nothing.
No payment
Join the list instead. We will write when the architecture is published, when the beta opens, and once at launch. Nothing else, and we will not pass your address to anyone.