Modelo 100 in Spain: Everything You Need to Know About Filing Your 2024 Tax Return

Starting in April, Spain launched its annual tax campaign. It’s time to file your Modelo 100 — the personal income tax return. This obligation applies to both Spanish citizens and foreign residents living in Spain on a regular basis. If you want to avoid overpaying or facing fines, it’s important to take this seriously.

Our mission is to save you time, money, and stress by handling the process for you.

What is Modelo 100 and Who Needs to File It?

Modelo 100 is the official form individuals use to file their annual personal income tax return (IRPF – Impuesto sobre la Renta de las Personas Físicas). The Spanish tax agency (Agencia Tributaria) uses it to calculate whether you owe additional taxes — or, in many cases, if you are entitled to a refund.

You are required to file if:

You have spent more than 183 days in Spain during the year (i.e., you are a tax resident);
You receive income from employment, self-employment (autónomo), rental properties, investments, or abroad;
Your income exceeds the legal thresholds, which vary depending on the source.

Even if you think “taxes are already withheld from my salary” or “I don’t need to file,” the truth is you might be overpaying or putting yourself at risk of penalties due to missing or incorrect information.

Can the Tax Agency Actually Owe You Money?

Yes! Filing your return doesn’t always mean you have to pay more. Quite the opposite — you may be eligible for a refund.

For example, if you are employed, your employer withholds income tax (IRPF) every month. However, these withholdings do not consider individual factors such as:

Family situation,
Mortgage payments,
Dependent children or relatives,
Eligible deductions.

When you file your return, the tax agency recalculates everything. If too much tax was withheld, you’ll get a refund. In addition, Spain offers a wide range of deductions — for children, dependents, donations, and more — which can further increase your refund.

Deadlines for Filing Modelo 100 in 2025

The 2024 IRPF campaign (for income earned last year) runs as follows:

Online filing: April 3 – July 1, 2025
Phone or in-person filing (with appointment): May 8 – July 1, 2025

Important: The earlier you file, the sooner you’ll receive any refund — and the less likely you are to make mistakes under pressure.

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Filing may seem simple, especially when using the borrador (pre-filled draft), but that’s exactly how people end up losing hundreds — or even thousands — of euros. Here are the top mistakes:

Not declaring foreign income

If you rent out property abroad or receive a salary in a foreign bank account, that income must be declared in Spain. People often:

Omit foreign income,
Declare it incorrectly,
Fail to apply double taxation treaties.

Ignoring deductions

Many taxpayers miss out on deductions for:

Renting a home,
Children and education expenses,
Pension contributions,
Charitable donations, and more.

This is money left on the table due to a lack of awareness.

Blindly trusting the borrador

The pre-filled form from the tax agency may not reflect your real expenses, deductions, or income sources. By signing it without review, you assume full responsibility for any errors.

Choosing the wrong filing method

In some cases, filing a joint return is more advantageous — especially for couples. But without a proper review, it’s hard to know which option benefits you most.

Missing the deadline or not filing at all

Forget to file, or think “I probably don’t need to”? You may face fines. Even if the tax amount is zero or minimal, filing is still a legal obligation.

Don’t Delay — Save Time, Money, and Headaches

The sooner you file, the sooner you can stop thinking about taxes and get back to what matters. And if you’re entitled to a refund — you’ll receive it without delay.

Book a consultation with our tax specialists today!