The tax calendar for your startup, month by month

The administrative year of a startup is entirely predictable, which means it can be planned. Here is every recurring deadline for a BV in one place, what happens if you miss one, and which parts stay with you.

Why a calendar beats a reminder

The administrative year of a startup is predictable. That is good news, because it means you can plan it instead of reacting to it. Most penalties we come across are not caused by someone not knowing a rule, but by a deadline landing on the same week as a release, a round or a holiday.

Below is the whole year for a BV whose financial year equals the calendar year. If your financial year differs, the annual deadlines move with your own year-end.

Monthly

• Payroll taxes: you file monthly or every four weeks as soon as you have staff or pay yourself as director-shareholder. The Belastingdienst publishes the exact filing and payment dates per period in a table.
• VAT, if you file monthly: by the last day of the following month.
• ICP declaration, if you report monthly: by the last day of the following month.
• WBSO hours, if you use the scheme: recorded within ten working days. Not a return, but a deadline you cannot repair.

Quarterly

• VAT first quarter: by 30 April.
• VAT second quarter: by 31 July.
• VAT third quarter: by 31 October.
• VAT fourth quarter: by 31 January.
• ICP declaration quarterly, if you meet the conditions: the same dates as the VAT return.
• WBSO project administration: updated within two months after each quarter.

Annually

• 31 March: the mandatory WBSO notification for the previous year, if you held an S&O declaration.
• 1 June: the corporate income tax return for the previous financial year. Request an extension and it generally moves to 1 November. The request has to be in within five months of your year-end.
• Within twelve months of your year-end: file the annual accounts with the KVK. For a calendar financial year that is 31 December of the following year at the latest.
• Provisional corporate tax assessment: request or amend it as soon as you know profit will be higher or lower, so you are not paying tax interest afterwards.

What happens if you are late

For VAT and payroll taxes, filing or paying late leads to a penalty, and an additional assessment can carry tax interest. Corporate income tax works differently: there the main effect is tax interest, which runs from a fixed moment after the financial year even if you have an extension.

Filing the annual accounts late is its own category. It is an economic offence, and in a bankruptcy a breach of the publication duty can be held against a director as improper management. Of all the deadlines here, that is the only one with a personal tail.

How we guard this

These deadlines sit in our planning, not in someone memory. We file the VAT, payroll and corporate tax returns on your behalf, handle the ICP declaration, submit the WBSO notification and actively remind you of the things only you can do, such as your hour registration. What stays with you, you know up front.

Deadlines and thresholds can change per year. The dates above are those of August 2026, with the official pages listed at the end of this article. If you are unsure about your own situation we check it or point you to someone who can.

In short

• Monthly: payroll taxes, plus VAT and ICP if you file monthly.
• Quarterly: VAT on 30 April, 31 July, 31 October and 31 January.
• Annually: WBSO notification before 31 March, corporate tax return 1 June with extension to 1 November, annual accounts filed within twelve months.
• Filing or paying late costs a penalty or tax interest; filing the annual accounts late is an economic offence.
• A non-calendar financial year moves every annual deadline with it.