Your first payslip of 2026 brings a surprise: why IRPF changed and how to check your tax‑w

What happened to IRPF on your first payslip of 2026

If your January (or first) payslip of 2026 looks different from last year, you are not alone. Employers update payroll settings at the start of a calendar year to reflect new rules, changed tables or fresh data from employees. A higher or lower IRPF withholding (the payroll tax retained for the personal income tax, IRPF) can result from administrative updates, changes in your personal situation provided to HR, or from modifications to the official withholding procedure.

This article explains the most common reasons behind the change, shows exactly what lines to check on your payslip, and gives practical steps to verify whether your employer is retaining the correct amount for 2026. All guidance is Spain‑centred and refers to official AEAT resources for withholdings.

Key official facts you should keep in mind

• Tax year: 2026 — the guidance and checks below are intended for 2026 payrolls.
• Minimum Interprofessional Wage (SMI) used as a context figure: 1,221 EUR/month if paid in 14 payments; 17,094 EUR/year.
• Social Security maximum contribution base (reference figure): 5,101.20 EUR/month.
• Example employee contribution item sometimes shown in payslips (MEI): 0.15% (this value appears as a standard employee line in some payroll items).
• If you use an online calculator or simulation on third‑party sites (including our calculator), remember: it is an informative simulation; the official withholding to compare with is the one published by the Agencia Tributaria (AEAT).

Official AEAT guidance on withholdings is here: https://www3.agenciatributaria.gob.es/Sede/Retenciones.shtml

Why your IRPF withholding may have changed

1. Employer updated withholding tables or payroll software for the 2026 tables and parameters. Payroll runs at year start usually apply updated legal or administrative rules.
2. Your declared personal circumstances changed or were re‑entered to payroll: marital status, number of dependants, disability, or other family situations directly affect the calculated withholding percentage.
3. Changes in salary structure: moving items between regular monthly salary and extraordinary payments (prorrata) or changing bonuses that alter the monthly taxable base will change the withholding amount.
4. Adjustment after a previous year correction: employers may apply a corrected rate if last year’s data were incomplete.
5. Social Security base updates or categories changed — contributions and the taxable base reported by payroll determine the net withholding calculation.

Note: AEAT publishes the rules and tables for employer withholdings; consult the official page above for the formal rules and any downloadable tables or instructions.

Which lines of your payslip to check (step by step)

1. Gross salary (Salario bruto): the starting point for payroll calculations. Make sure it matches your contract or recent payroll notice.
2. Social security contributions (Cotizaciones a la Seguridad Social): check the total employee deductions and any breakdown lines. The social security ceiling (maximum base) is a reference for contributions but employers show the actual base used each pay period.
3. Taxable base for IRPF (Base de retención): this is the amount on which your employer applies the withholding percentage. It should reflect gross salary minus social security employee contributions and other permitted deductions.
4. Applied withholding percentage (Tipo de retención): the percentage your employer uses to calculate the IRPF deduction. If the payslip shows only the final euro amount of withholding, ask HR for the percentage used.
5. Monthly withholding amount (Retención IRPF): the euro amount withheld that appears as a deduction line.
6. Extraordinary payments and prorrata: if your contract has 14 payments, extra pay is often prorated monthly; check if the employer treated extras differently this year.

How to verify whether your employer is retaining correctly

1. Ask HR or payroll for the withholding percentage they used and the inputs: declared family situation, number of children, disability, and any other relevant data.
2. Recreate the base taxable amount: gross salary minus employee social security contributions (confirm the base amounts shown on the payslip).
3. Use our net‑salary calculator as an informative simulation to estimate withholding (remember: it is only an estimate). Official validation must be done against AEAT guidance.
4. Compare the employer’s withholding percentage with the result from the AEAT retention rules or the AEAT guidance page. If you suspect a mistake, request a written explanation from HR with the formula used.
5. If the difference is substantial, discuss it with payroll and, if unresolved, refer to AEAT instructions or contact Agencia Tributaria for clarification.

Practical tip: small variations can arise during the first payrolls of the year while employers synchronise updated datasets. However, persistent errors across several payslips merit a formal check.

Common scenarios and what to do

• Your withholding increased: confirm whether your declared personal situation changed, whether payroll software applied different tables, or whether a one‑off bonus was included in the taxable base.
• Your withholding decreased: ensure the lower retention was intentional and based on updated family or personal information; a too‑low retention can lead to a larger tax bill at income‑tax time.
• Payslip shows unusual deduction lines: ask payroll for a line‑by‑line explanation and the legal basis.

When to seek outside help

This article does not provide legal advice. If payroll cannot resolve a discrepancy or you suspect a systematic error, you may consult a tax technician or use AEAT resources for additional guidance. The AEAT pages on withholdings include official rules and contact options for taxpayers.

Use our calculator (informative) — quick checklist

• Enter your gross salary and number of payments (12 or 14) and confirm the SMI context: 1,221 EUR/month in 14 payments (17,094 EUR/year).
• Enter permanent deductions shown on your payslip (social security employee contributions and any specific MEI line; a common example entry is 0.15%).
• Compare the simulated withholding with the one on your payslip.

Remember: the on‑site calculator provides an informative simulation. The official withholding to be compared is the one from AEAT and your employer’s payroll. Always reconcile the simulation against your actual payslip and AEAT guidance.

Official sources and next steps

See Agencia Tributaria — Withholdings (Retenciones): https://www3.agenciatributaria.gob.es/Sede/Retenciones.shtml

If after checking you still doubt the withholding, request a written breakdown from HR and, if needed, consult AEAT or a qualified tax technician. Keeping copies of payslips and written communications will help resolve discrepancies.

Spain‑focused disclaimer

This article is focused on payroll withholding in Spain for the 2026 tax year and is for informational purposes only. It does not constitute legal, tax or professional advice. For official tables, rules and personalised determinations consult the Agencia Tributaria and authorised tax professionals.

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