When Does a Private Sale Become a Business Activity?

A single private sale — for example of a website you've spent your free time building — is different from running an ongoing business. But the line between the two can shift faster than many expect, and misunderstanding it has real tax consequences in Denmark.

The VAT registration threshold: DKK 50,000

The most concrete threshold to know is the VAT registration threshold of DKK 50,000 in revenue within a rolling 12-month period — not a calendar year. If you expect to exceed this amount, you must register for VAT no later than 8 days before the threshold is reached. This applies regardless of whether you consider the activity a "hobby" or a private project — exceed the threshold, and you're required to register for VAT.

It's not just about the amount

Beyond the threshold itself, the Danish tax authorities look at a number of other factors when assessing whether an activity actually constitutes a business:

• Regularity. Is it a one-off sale, or does it happen repeatedly over time?
• Intent to profit. Is the activity carried out with the aim of creating ongoing earnings, or is it a one-time disposal of something you've used or built yourself?
• Active marketing and sales. Do you systematically market and sell — for example by repeatedly buying and reselling, or by actively seeking out buyers? That points toward a business activity, regardless of whether you formally have a business registration.

Example: from private to commercial

If you sell a single website or webshop you've run yourself, that's generally a private, one-time disposal. But if you start building, growing and selling several websites or webshops in the same pattern, repeatedly, with the aim of generating income from it, the activity quickly starts to resemble a business — even though each individual sale might look like a private deal on its own.

Why it matters

If an activity is assessed as a business, but you haven't registered or accounted for VAT along the way, you risk having to pay VAT retroactively on deals already completed — often without being able to charge it to buyers who've already paid. This can be an expensive mistake to discover too late.

Not sure?

There's no single criterion that decides the matter alone — it's an overall assessment. If you're even slightly unsure whether your activity is approaching business status, it's far cheaper to get it clarified with an accountant in advance than to fix it after the tax authorities have raised the question.

Frequently asked questions

How much can I sell for before I need to register for VAT?

The threshold is DKK 50,000 in revenue within a rolling 12-month period. If you expect to exceed it, you must register no later than 8 days before the threshold is reached.

Does it count as a business if I only sell once?

Generally no — a one-off, private sale is different from an ongoing activity. But if you repeat the pattern several times with the intent to profit, that can quickly change the assessment.

What happens if I should have registered for VAT but didn't?

You risk having to account for VAT retroactively on sales already completed, often with no way to charge it to the buyers involved afterward. If you're unsure about your situation, get it clarified with an accountant in advance.

Read more about selling a website privately to a company, or about the specific considerations when selling a webshop privately.