Guide

#What the prepayment register is

The prepayment register is a register maintained by the Finnish Tax Administration that lists companies and entrepreneurs who take care of their own taxes through prepaid tax (ennakkovero). Being listed tells the party ordering the work one practical thing: they don't need to withhold tax from a fee paid to a registered party, because paying the taxes is the recipient's own responsibility.

If the person doing the work isn't in the register and invoices the fee directly under their own name, the payer becomes obligated to withhold tax and report the payment to the Tax Administration. This is exactly the hassle companies want to avoid, which is why being listed in the register matters a great deal in business-to-business dealings. You can find the detailed rules on vero.fi.

The purpose of the register is to make life predictable for the payer. When a company orders work from another company, it can confirm with a single check that no withholding obligation applies to the payment. At the same time, the registration acts as a mark of reliability: it shows that the entrepreneur has handled their tax obligations properly, since the Tax Administration can remove anyone who neglects them from the register. That's why many buyers routinely check the registration before signing a contract, much like checking credit information.

The prepayment register, the Trade Register, and the VAT register are often confused in everyday conversation, even though they're separate things. The Trade Register confirms that a company exists, the VAT register confirms VAT liability, and the prepayment register specifically concerns withholding tax. As a light entrepreneur, you don't need to master these distinctions for a living, but knowing the basics helps when a client asks about registrations during a sales conversation. In this guide we'll focus on just one of them — the prepayment register — and what it actually means for you.

#Why your client asks about the prepayment register

Business clients routinely check their partners' registrations, often via ytj.fi. So a question about the prepayment register isn't a sign of distrust — it's a normal part of the purchasing process: the buyer just wants to make sure that paying your invoice won't create unexpected withholding or reporting obligations.

As a light entrepreneur, you can answer with confidence: invoicing runs through an invoicing service, so the client's contractual counterparty on the invoice is a company, not a private individual. For the client, the situation is just as effortless as paying any other company's invoice.

A practical example: you build a website for a local company, and the buyer asks whether you're in the prepayment register. You explain that you invoice through an invoicing service, so the invoice comes from Truster and taxes are handled as part of the payroll process. For the buyer, this means they pay a normal business invoice with no withholding obligation or extra paperwork. Most companies are already familiar with this arrangement and find it a fully adequate answer, since a large number of professionals in Finland work through invoicing services.

If your client is a private individual, the prepayment register comes up less often, but it still matters behind the scenes: for example, a client applying for the household expenses deduction (kotitalousvähennys) needs an invoice from a provider that handles its tax obligations properly. A light entrepreneur's invoice satisfies this need too, since Truster acts as the invoicing party. So you don't need to explain the register's details to your client — it's enough to say the invoice comes from an invoicing service. If the client wants confirmation, they can check it themselves on ytj.fi in a couple of minutes, and that settles the matter.

#How this works with light entrepreneurship

When you invoice through Truster, your client pays the invoice to Truster. Truster then pays you wages for your work, withholds tax from that pay according to your tax card, and takes care of the statutory reports. So you don't need to register for the prepayment register, pay advance taxes, or file business tax returns, because you're operating without a company of your own.

From the client's perspective, this arrangement removes the whole withholding question: they pay the invoice sent by the company, with nothing to withhold and no reports to file. That's one reason a light entrepreneur's invoice is easy for a business client to accept.

For you, in practice, this means three things: keep your tax card up to date in OmaVero (the Finnish Tax Administration's online service), track your payslips in the app, and let Truster handle the reporting. Your pay information is reported to the authorities as part of the payroll run, so you don't need to file separate reports on your gig income. At the end of the tax year, you simply review your pre-completed tax return, just as any employee would. So the amount of red tape doesn't increase, even with several income sources.

#The sole proprietor's perspective

If you operate under your own Business ID (Y-tunnus), things change: a sole proprietor (toiminimi) usually registers for the prepayment register themselves, typically as part of the start-up notification through the YTJ Business Information System. An entrepreneur listed in the register pays their taxes as prepaid tax, which the Tax Administration sets based on an estimated result. The Tax Administration can also remove the entrepreneur from the register if reporting or payment obligations are neglected.

With Truster's sole proprietorship service, you get your own Business ID while keeping the ease you're used to from light entrepreneurship: Truster helps with registrations and handles invoicing and paperwork on your behalf. The sole proprietorship service costs 3.99% of invoicing or €59/month.

Being registered also shifts some responsibility to the sole proprietor: prepaid taxes are based on your own income estimate, which you need to remember to update when your income changes, and you must file a business tax return every year. This isn't overwhelming, but it's good to be aware of before choosing a model. Many entrepreneurs start out as light entrepreneurs and only move to a sole proprietorship once their business has stabilized and income is predictable.

The idea behind prepaid taxes is simple: since no one automatically withholds tax from a sole proprietor's income, the Tax Administration sets the tax to be paid in advance based on an estimated result. If the year turns out better or worse than expected, it's worth updating the estimate in OmaVero so the taxes paid match reality. This is the biggest practical difference compared with light entrepreneurship: a light entrepreneur's taxes are handled via the tax card as part of payroll, with no action required, while a sole proprietor tracks their own income throughout the year.

#Which model suits you

Light entrepreneurship suits you when you want to invoice for your work without a company of your own and let Truster handle taxes, reporting, and registration matters. Your own Business ID and registering for the prepayment register become relevant, for example, when you do work that requires a permit or when your clients require you to have your own company.

The good news is that the choice isn't permanent. You can start as a light entrepreneur and move to a sole proprietorship once your business grows, and Truster supports you at both stages. You can always find the details of the prepayment register and up-to-date instructions on vero.fi.

In short: the prepayment register is primarily a tool for the payer, not something for you to worry about. As a light entrepreneur, you can tell your client that invoicing runs through an invoicing service and taxes are handled automatically as part of payroll. As a sole proprietor, you take care of the registration yourself, and Truster helps you with that too. Either path leads to the same result: your client can pay your invoice with no worries, and you get paid for your work without any tax surprises.