Before you start

Passport, for a prepaid SIM
NIE and a Spanish bank account, for a contract
An unlocked or eSIM-capable handset
A Spanish address, for fibre installation

Step-by-step

1
Buy a prepaid SIM on your passport on arrival
Available at the airport, phone shops and supermarkets. Registration against your passport is required by law. A Spanish number in your first hour unlocks bank verification and appointment systems.
In personWho: YouDay 1
2
Wait for the NIE before taking a contract
Contract tariffs need a NIE and usually a Spanish IBAN for the direct debit. They are considerably better value than prepaid and typically bundle mobile with fibre, but there is no way around the identity requirement.
In personWho: You
3
Bundle fibre with mobile, which is how Spain prices it
Spanish operators price convergent bundles aggressively and mobile alone is poor value. Fibre coverage across Donostia is good and symmetric gigabit connections are ordinary.
OnlineWho: You
4
Check coverage for the valleys and the coast
Gipuzkoa is steep and folded, with settlements in narrow valleys and a mountainous interior. Coverage can fall away sharply a few kilometres from a well-served town, and the operators differ substantially in which valleys they cover. This matters more here than in flat Spain, because so much of the weekend life is in the hills.
OnlineWho: You
5
Understand what happens near the French border
Handsets in Hondarribia, Irun and on the eastern beaches routinely register on French networks. Within the EU roaming rules this is generally free, but call-forwarding, some fixed-line services and any non-EU plan can behave unexpectedly. If you cross the border regularly, check your tariff's small print rather than assuming.
OnlineWho: You
6
Check the risers in older buildings before assuming fibre
Getting fibre into a nineteenth-century building in the Parte Vieja or the Centro depends on the existing risers and sometimes on the building community's agreement. Ask what is already installed before signing a lease if a fast connection matters to your work.
OnlineWho: You

Documents you’ll need

Passport, for prepaid registration
NIE and Spanish IBAN, for a contract
Proof of address, for fibre

Things most newcomers don’t know

There is no anonymous SIM in Spain, unlike the UK.

Every Spanish SIM must be registered against an identity document at activation. A passport is enough for prepaid, so this is not a barrier — but arriving expecting to buy one off a supermarket shelf and use it immediately means an unexpected counter visit with documents in hand.

Source: Ministerio para la Transformación Digital

Euskaltel's legacy means local coverage differs from the national picture.

The Basque Country had its own regional telecoms operator for decades, which built out cable and fibre in places the national incumbent reached more slowly. It is now part of a larger group but the infrastructure legacy remains, and coverage and pricing in Gipuzkoa do not always match what national comparison sites suggest. Check locally rather than assuming the Spanish average applies.

Source: Comisión Nacional de los Mercados y la Competencia

Terrain, not population, drives mobile coverage in Gipuzkoa.

The province is steep and folded, with towns strung along narrow valleys and a mountainous interior. Coverage can drop sharply a few kilometres from a well-served town, and the four networks differ substantially in which valleys they serve. Since the valleys are where the sidrerías, the walking and much of the industry are, this is a practical choice rather than a technicality.

Source: Comisión Nacional de los Mercados y la Competencia

Spanish fibre is genuinely excellent and cheap, which surprises people.

Spain has among the highest full-fibre coverage in Europe, well ahead of Germany or the UK, and symmetric gigabit connections are ordinary and inexpensive. For remote workers this is one of the strongest and least advertised practical arguments for the country, and Donostia is well served within it.

Source: Comisión Nacional de los Mercados y la Competencia

Common mistakes to avoid

Expecting to buy an anonymous SIM as in the UK.
Signing a long contract before you have a NIE and being pushed onto a worse tariff.
Choosing a network on city performance without checking valley coverage in Gipuzkoa.
Assuming fibre is available in an old Parte Vieja building without checking the risers.
Cancelling your old service before porting the number.

Some of this may be out of date. Spotted something inaccurate? Help us keep it right for the next newcomer.

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