Modelo 210: the 12 most common mistakes (and how to avoid them)

Modelo 210 looks simple: a value, a percentage, a rate. Yet we regularly see the same mistakes — some harmless, others that cost a recargo, a returned transfer or a letter from the tax authority. Here are the twelve most common, with their cost and the right approach.

Fiscasa is a private service, independent of the Agencia Tributaria. The amounts are illustrative.

1. Filing a single return for a couple

The mistake: Paul declares 100% of the imputed income on the flat he owns 50/50 with Mary, in his name alone.

Why it's a problem: each co-owner is a separate taxpayer. Mary has declared nothing, and Paul has declared a base that isn't his. Even if the total amount paid is right, Mary's position has not been regularised and Paul's is inaccurate.

The right approach: one return per co-owner, each for the share shown in the title deed.

2. Declaring 100% for each spouse

The opposite mistake: each declares the whole property.

The cost: the tax is paid twice. On a property with a cadastral value of €60,000 at the 2% rate, that is €228 paid instead of €114 each (at 19%; at 24% for UK residents, €288 instead of €144).

The right approach: check the ownership share in the escritura. The overpayment can be recovered with a request for rectification within four years.

3. Forgetting to apportion in the year of purchase or sale

The mistake: declaring a full year for a property bought on 1 October.

The cost: on annual tax of €200, you pay €200 instead of €50.41 (92 days out of 365).

The right approach: count the actual days of ownership, allowing for leap years (366 days in 2024 and 2028).

4. Forgetting the garage or storeroom

The mistake: declaring only the home when the garage has its own cadastral reference.

The cost: for a garage with a cadastral value of €7,500 at the 2% rate, that is €28.50 of undeclared tax a year (€36 for a UK resident). Nothing dramatic, but over four years and with a recargo, catching up costs more than filing in the first place. And the new 2027 form, which asks for the cadastral reference, will make the omission more visible.

The right approach: gather all the IBI bills in your name. One bill, one reference, one calculation.

5. Applying the wrong rate (1.1% instead of 2%, or vice versa)

The mistake: applying 1.1% because "the value was updated this year", or 2% by default without checking.

The cost: on a cadastral value of €80,000, the difference in tax is €136.80 a year per property at 19% (€304 versus €167.20).

The right approach: the 1.1% rate only applies if the municipality has had a general cadastral revision that came into force on or after 1 January 2012. Annual update coefficients do not count. See imputed income on a property you don't let.

6. Using the wrong figure on the IBI bill

The mistake: taking the base liquidable, the land value alone or the value for another year.

The right approach: use the total valor catastral for the year being declared. See IBI.

7. Applying 19% when you live in the UK (or 24% when you live in Ireland)

The mistake: a UK resident keeps using the 19% EU rate they applied before Brexit; an Irish resident with a non-EU passport thinks they must pay 24%.

The right approach: it is tax residence that determines the rate, not nationality. 19% for residents of the EU and EEA (including Ireland), 24% for everyone else — including UK residents since 2021. UK residents also cannot deduct expenses from rental income.

8. Getting the transfer reference wrong

The mistake: writing "IRNR 2025 Y1234567X" or adding your name next to the payment ID.

The cost: the transfer is sent back, the debt is not paid, and if the deadline passes in the meantime, a recargo applies.

The right approach: the reference must contain only the payment ID. One transfer per return. See paying from the UK or Ireland.

9. Letting the payment ID expire

The mistake: generating the return in November and paying in January.

The right approach: the ID is valid for 30 calendar days. Pay straight away, or generate a new payment document.

10. Paying on the last day

The mistake: a transfer sent on 31 December.

The cost: the payment date is the date the funds arrive. A payment credited on 3 January is late: 1% recargo. International transfers from the UK can take longer than a SEPA transfer from Ireland.

The right approach: pay at least a week before the deadline. And from 2027, watch out for the new calendar: 2026 imputed income cannot be filed before 1 April 2027 (see what's new in 2027).

11. Confusing letting with imputed income

The mistakes:

• declaring imputed income for a property let all year;
• forgetting the imputed income for the days not let on a holiday let;
• deducting expenses (IBI, community fees) from imputed income, which is not allowed;
• deducting 100% of the annual expenses for a two-month let, instead of the pro rata share (and only if you are an EU/EEA resident).

The right approach: split the year into days let and days not let, and apply each period's rules. See letting.

12. Thinking someone else is taking care of it

The mistake: assuming the notary, the estate agent, the community administrator or the bank that pays the IBI also files the Modelo 210.

The reality: unless you have given an explicit mandate, nobody does it for you. The tax authority doesn't send tax assessments. If you have no record of a return (signed document, proof of payment), assume nothing has been filed and check. If years are missing, see filing late years.

Bonus: mistakes on the UK or Irish side

• Declaring imputed income at home: generally pointless — it is not income for UK or Irish tax purposes, and the Spanish tax on it cannot be credited.
• Forgetting Spanish rent on the SA106 (UK) or your Form 11 / Form 12 (Ireland).
• Expecting a full credit for the 24% Spanish tax paid on gross rent: the UK credit is capped at the UK tax on the same income.

See declaring Spanish property income in the UK and Ireland.

Our method for avoiding these mistakes

At Fiscasa, every return goes through a checklist: ownership share checked in the deed, days recalculated, cadastral references listed, the municipality's rate checked, residence rate checked, payment ID and reference explained in English. If a calculation error on our part leads to a surcharge or interest, our written guarantee provides for their reimbursement, within the conditions and limits of our terms of sale. See our pricing and the calculator.

FAQ

I made a mistake in a return I've already filed. What should I do?

If you paid too much, a request for rectification lets you recover the difference within four years. If you paid too little, a voluntary supplementary return limits the cost to a recargo.

My transfer was returned. Is my return valid?

The return exists, but the tax has not been paid. Generate a new payment document and pay as soon as possible.

Do I have to declare a garage bought with the flat?

Yes, if it has its own cadastral reference and its own IBI bill. If it is included in the home's reference, it is already taken into account.

Does the pro rata count the day of purchase?

The calculation is based on days of ownership in the year. Calculation tools generally treat the date of the deed as the first day of ownership; a one-day difference amounts to a few cents.

Can a return be corrected after 1 January 2027?

Yes. Any supplementary or rectification return filed from that date uses the new form.

Does Fiscasa check returns prepared by another provider?

Yes, we can review your returns for past years and point out any discrepancies before preparing the next ones.