.si Domain

What is a .si domain?

.si is the internet country code of Slovenia. It has existed since April 1992 and is run by Register.si, a service of ARNES, the country’s academic and research network.

It is not limited to Slovenians. The registry’s terms define a holder only as a person or a company, with no residence or local-entity requirement, so a .si name can be registered from anywhere through any of the registry’s accredited registrars, or through registrars that resell them.

Outside Slovenia, people pick .si for what the letters read as: “sí” is “yes” in Spanish and Italian, and in 2026 “SI” became shorthand for super intelligence.

Why .si domains became popular in 2026

On 22 September 2026 President Trump told the UN General Assembly that the United States would replace “AI” with “super intelligence”, and on 29 September he signed Executive Order 14434, which tells federal agencies to use “Super Intelligence” or “SI” in place of “AI”.

Registrations followed the news. In the twelve months before, .si gained between 2,324 and 6,938 new names a month; in September 2026 it gained 46,066, and on 4 October alone 13,651. By 6 October the registry counted 311,632 .si domains in total.

Much of the rush is speculation. Netcraft found that more than half of the .si names registered at Dynadot between 19 and 22 September were listed for resale, and that about 22% of new .si names match an existing .ai domain. The registry itself has called the surge unprecedented while warning against comparing .si with .ai.

Recursive.si

Sold for $20,000 in May 2026, to an AI company of the same name

AI.si

Listed for sale at $699,995 — an asking price, not a sale

Is .si good for SEO? .si compared with .ai

Google treats some country codes as generic, so a site on them can rank anywhere: .ai, .io, .co and .me are on that list. .si is not. Google reads a .si site as aimed at Slovenia unless other signals say otherwise.

For a product with a worldwide audience that means a .si address starts with a disadvantage in search that a .com or .ai does not have. For a brand name, a short link, or a site for Slovenia it does not matter.

The two endings are also one key apart on a QWERTY keyboard. If your brand already lives on .ai, the matching .si is worth registering before someone else does.

How to choose where to register .si

Accredited registrars all pay the registry the same €10 a year, so a first year around $12 is close to cost and anything below it is a promotion. Compare the renewal column: that is the price you will pay every year after the first, and it varies more than the first year does.

Watch for a low first year paired with a steep renewal. EuroDNS, for example, lists a first year at €12.99 and a renewal at €76.50.

You can register for at most 5 years at a time, so a ten-year plan means renewing at least once. Transfers between registrars keep the expiry date and need the domain’s authorisation code.

Rules to know before you register

These come from the registry’s general terms, which every .si registrar works under.

Verification

At registration and renewal the registrar must confirm the holder’s email or phone, and may ask for identification depending on its risk checks.

Changing your mind

A new name can be returned within 16 days if no name servers have been set yet.

Transfers

Done with an authorisation code. Uniquely for .si, the current registrar is given a SHA-256 digest of the code and the new one the code itself.

Expiry

An unrenewed name stops resolving and spends 30 days in quarantine, when it can still be renewed. Then it is deleted and anyone can register it.

Reserved names

A short list is held back, such as 112.si and 113.si (emergency numbers) and si.si.

Security

DNSSEC has been supported since December 2011, and Registry Lock is available for names that need it.