Field note · Private clients
Families abroad almost always believe the clock starts when they find a lawyer. It starts on the day of death, and it has already been running for weeks by the time most people write to us.
Spanish inheritance tax is self-assessed and it is due within six months of the date of death. Nobody sends a reminder. There is no filing that happens automatically because a notary or a bank is involved. If the six months pass, the position gets worse every month, and it gets worse in two different taxes at once.
The six months, and the one extension
The ordinary period is six months from death. An extension of a further six months can be granted — but it has to be applied for within the first five months. Not the sixth. Miss that window and the extension is simply not available, whatever the reason.
The extension is not free. Late-payment interest runs on the tax from the end of the ordinary six-month period. What it buys is time to gather documents without the surcharge regime biting, which for a foreign family is usually what is actually needed.
What has to be gathered, and how long it really takes
The list looks short. From outside Spain it is not.
- Death certificate. If the death occurred abroad, it needs an apostille and a sworn translation into Spanish. Both take longer than the family expects.
- Certificate from the Central Register of Wills (Registro General de Actos de Última Voluntad), which cannot be applied for until fifteen working days have passed since the death. That is a fixed delay built into the start of the process.
- The will, and an authorised copy of it. If there is a foreign will, it has to be examined against the Spanish assets and, depending on the case, an act of declaration of heirs may be needed instead.
- A Spanish tax identification number (NIE) for every heir. Individually applied for, from abroad usually through the consulate or by power of attorney. This is the single most common cause of delay.
- Powers of attorney if the heirs are not travelling to Spain, again apostilled and translated.
- Bank certificates of balances at the date of death, land registry information, and valuations for each asset.
None of this is difficult. All of it is sequential, and several steps run through foreign consulates and registries whose timetables you do not control. Six months is not a generous period. It is a tight one.
Why the region changes the bill
Spanish inheritance tax is state law with substantial regional variation. The same estate, the same heirs and the same relationship can produce very different tax depending on which autonomous community’s rules apply — the difference between regions is frequently measured in tens of thousands of euros, not percentage points.
Which rules apply depends on the facts, not on choice. Where the deceased was not resident in Spain, the rules of the autonomous community in which the greatest value of the Spanish estate is located apply. Where the deceased was resident in Spain, it is the rules of the community where they were resident.
One point that still surprises foreign heirs: since the reform made by Act 11/2021 of 9 July, non-resident heirs can apply the regional rules whether or not they live in the European Union. The old discrimination against residents of third states, which the Court of Justice condemned in 2014 and the Spanish Supreme Court dismantled afterwards, is gone from the statute. If an estate was settled on the old basis, there may be tax to reclaim.
What happens if the deadline passes
If you file late but before the tax authority asks you to, the surcharge under article 27 of the General Tax Act is 1% plus a further 1% for each complete month of delay, up to twelve months. From twelve months, it is 15% plus late-payment interest.
If the authority gets there first — if a formal request arrives before you file — you are no longer in the surcharge regime. You are in the penalty regime, which is a different and worse conversation.
The second clock nobody mentions
Municipal capital gains tax on urban land, the plusvalía municipal, is a separate tax with its own separate deadline: six months from the death, extendable to one year on request. It is charged by the town hall where the property sits, it has nothing to do with the inheritance tax filing, and it is missed constantly because families assume one filing covers everything.
Two properties in two municipalities means two filings, on two sets of municipal rules.
The practical point
If someone has died and there are assets in Spain, the useful first step is not valuing the estate. It is starting the NIE applications and ordering the certificates, on day one, in parallel, before anyone has decided anything about who takes what. Everything else can be done later. Those cannot.
This is general information on Spanish law as at 31 August 2026, not advice on your situation, and regional rules change frequently. If a death has already occurred and there are Spanish assets, the clock is running: submit your project and say when the death occurred, and you will have an answer within two working days.