If you pay tax late or file your return late, the tax authorities can charge tax interest. That interest can add up considerably and is an unnecessary cost. This article explains how tax interest works and how to avoid it.
What is tax interest?
Tax interest is interest the tax authorities charge if you pay tax later than intended. This happens, for example, if you file your return late or if it later turns out you paid too little. The interest runs over the period the amount was outstanding.
When do you get tax interest?
You risk tax interest with income tax and corporate tax if your final assessment leads to an additional payment imposed after a certain date. Also with a late or incorrect VAT return that you correct with a supplementary return, interest can be charged.
How do you avoid tax interest?
The best way is to file and pay your return on time and in full. If you expect an additional payment with income tax, request a provisional assessment in time or have your existing assessment adjusted. That way you pay the right amount on time and prevent interest from accruing.
What do you do with a mistake?
If you discover you paid too little, correct it as soon as possible, for example with a supplementary return for VAT. The faster you fix it, the less interest accrues. Waiting only makes it more expensive. Tidy bookkeeping and timely filing are your best protection against unnecessary interest.
This article provides general information based on the rules known for 2026 and does not replace personal tax advice. For your specific situation, we're happy to take a look with you.
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