What is a business tax return?
A business tax return is an annual report to the Tax Administration showing how much your business earned and how much was spent on expenses. Based on this, the Tax Administration calculates whether you owe more tax or get money back.
Simply put: "Dear Tax Administration, this year I earned this much and spent this much. Please calculate my final tax."
Why does this concern me?
A sole trader business (toiminimi) is not a separate entity for tax purposes. Your business income is your personal income — just like salary. The business tax return tells the Tax Administration how much income and expenses came from your business activities.
This is separate from your personal tax return. PalkkaOnline handles the business tax return. Personal tax matters (salary income, mortgage interest deductions, etc.) you handle yourself in MyTax (OmaVero).
When is the tax return due?
The tax return is filed once a year. It covers the full previous year (January–December). The deadline is early April of the following year. The exact date varies annually.
Example: Income from 2026 → tax return filed in April 2027.
What does PalkkaOnline do?
Collects data automatically — All invoices, expenses, and VAT reports for the year are already in the system.
Prepares the tax return — Our accounting service compiles the data onto the official tax return form.
Sends it for review — You receive the tax return by email for review before submission.
Submits to Tax Administration — When you approve, PalkkaOnline submits the return on your behalf to MyTax (OmaVero) under the Suomi.fi authorisation.
Your job: review and approve. That is all.
What should I check?
Before approving, verify:
Income — Are all your invoiced jobs included? Is anything missing?
Expenses — Are all your expense receipts included? If you forgot to add an expense to PalkkaOnline, it will not appear on the tax return.
Tax prepayments — Does the correct amount of paid tax prepayments show?
Tip: If you are missing receipts, add them to PalkkaOnline BEFORE approving the tax return. The more accurate the data, the more accurate your taxation.
What happens after the tax return?
The Tax Administration processes the return and sends a tax decision. It shows:
Back taxes — If you paid too little tax prepayment during the year, you pay the difference as back taxes. This is normal, not a penalty.
Tax refund — If you paid too much, you get money back. This is also normal.
The tax decision is usually finalised between June and October.
What if I only started during the year?
If you started your business mid-year, the tax return is still filed. It only covers the months you were active. In the first year, income is often low and tax prepayments were based on estimates, so a tax refund is common.