Tax Return Deadlines: The Core Rule

The baseline rule

German income tax returns are filed for the previous calendar year. The standard deadline for self-filers is defined in §149 Abs. 2 AO (Abgabenordnung) as the last day of the seventh month after the tax year ends.

For the 2025 tax year (January 1 – December 31, 2025): the deadline is July 31, 2026.

This calculation is consistent: for any tax year, count seven months from December 31st of that year. The method does not change — the specific calendar date is the variable.

If you use a Steuerberater or Lohnsteuerhilfeverein

When a licensed tax advisor (Steuerberater) or wage tax assistance association (Lohnsteuerhilfeverein) submits on your behalf, the deadline extends to the last day of February of the second year after the tax year.

For the 2025 tax year: the extended deadline is February 28, 2027.

This extension is automatic when a licensed professional is involved — you do not apply for it. It applies because advisors file on behalf of many clients and the law accounts for this volume. Verify with your advisor that they are tracking the deadline on your behalf; do not assume silence means everything is on schedule.

Deadline reference table

Mandatory vs. voluntary filing

Not every employed person in Germany is required to file. Understanding which category you are in determines which deadline applies to you.

You must file (Pflichtveranlagung) if any of these apply:

• You had income from two employers simultaneously (not sequentially) in the same year
• You received Lohnersatzleistungen above EUR 410/year: Kurzarbeitergeld (short-time work), Elterngeld (parental benefit) above EUR 410/month, Krankengeld (sick pay), Mutterschaftsgeld (maternity benefit)
• You had freelance, rental, or investment income above EUR 410/year not already fully taxed at source
• You applied for a Lohnsteuerermäßigung (wage tax reduction) during the year
• You are married, both spouses work, and chose tax class combination III/V

You may file voluntarily (Antragsveranlagung) if none of the above apply. Voluntary filers have four years from the end of the tax year to claim a refund (Festsetzungsverjährung). For 2026: you can still file returns for 2022, 2023, 2024, and 2025. Expats who arrived mid-year and had full-year withholding deducted on a partial-year income almost always receive a refund.

If you are uncertain whether filing is mandatory, err on the side of filing. The downside of an unnecessary return is minimal. Missing a mandatory one is not.

What happens if you miss the deadline

Missing the self-filer deadline (July 31st) without requesting an extension triggers escalating consequences:

Up to 14 months late: The Finanzamt may send a reminder and request the return. First-time small delays often result in a letter rather than immediate financial penalties. However, since a 2016 reform, automatic penalties became law — the Finanzamt no longer needs to issue a separate warning notice.

Beyond 14 months late (mandatory filers): A Verspätungszuschlag (late filing surcharge) is assessed automatically: EUR 25 per month of delay, minimum EUR 25, maximum EUR 25,000 or 10% of the assessed tax amount — whichever is lower.

Interest (Nachzahlungszinsen): If you owe tax and file late, interest accrues on the unpaid amount at 1.8% per year (as of 2019 reform) from 15 months after the tax year ends.

How to request an extension

If you cannot file by July 31st, request a Fristverlängerung (deadline extension) from your local Finanzamt before the deadline, not after.

Write a brief letter or email to your Finanzamt explaining:

• Which tax year the return is for
• Why you need more time (document delays, travel, illness — specific reasons help)
• A proposed new deadline

Extensions of 1–2 months are commonly granted for credible reasons. Keep the written confirmation. There is no standard form — a short, clear request is sufficient.

The 4-year voluntary filing window in practice

Many recently arrived expats miss their first year or two of voluntary filings. The good news: you have four years to file them retroactively.

If you arrived in Germany mid-2023 and have not filed for 2023 yet: you can still file until December 31, 2027 for a refund. The average refund for employees is around EUR 1,000. Partial-year employees — those who started working in Germany mid-year — are especially likely to receive substantial refunds, because German payroll calculates as if the current income were earned the entire year.

File earlier rather than later: refunds are processed within 4–8 weeks of submission if done early in the year. Filing in July means the Finanzamt is processing at peak volume — expect longer wait times.

Practical calendar for employed residents

Filing in March or April instead of July reduces processing time and gets your refund faster. There is no advantage to waiting until the deadline.