The 7 most common small business accounting mistakes and what they cost

When we take over a new client's books, we check them first. And almost every time we find the same mistakes. They are rarely intentional, but in a tax audit that makes no difference: tax, late payment interest and fines are calculated the same way.

1. Invoices with incorrect details

A wrong buyer code or VAT number, or a missing date. Such an invoice has to be corrected, and the VAT deduction may be rejected.

2. Personal expenses paid by the company

Food, fuel for a personal car, holidays. Such expenses may be treated as the owner's income with all the taxes that follow.

3. Unrecorded card payments

Monthly subscriptions (software, online advertising) often have no invoices. Purchases from foreign suppliers may trigger a reverse-charge VAT obligation.

4. Mismatched i.SAF data

If your i.SAF data and your partner's do not match, the tax authority sends an enquiry. This is the most common reason small businesses receive letters from VMI.

5. Taking money out without a decision

A transfer to the owner without an MB member's decision or a dividend decision is later reclassified and taxed differently.

6. A cash register that does not match reality

The cash balance “on paper” is several thousand euros, but there is no cash in the till. For VMI this signals that money was taken out unrecorded.

7. Late documents

When documents arrive after the return deadline, the books are updated retroactively, which means amended returns.

What it costs

• Unpaid tax – you will have to pay it anyway.
• Late payment interest – charged for every day of delay.
• Fine – VMI may impose a fine whose size depends on the amount of unpaid tax. If you correct the mistake yourself before VMI finds it, the consequences are usually smaller.
• Time – amendments, explanations to VMI, balance reconciliations.

Advice from Ana Baranova, director of Patikima buhalterė: “Most of these mistakes are solved by one habit: submitting documents every month by the agreed date, not once a quarter. Then we spot a mistake straight away, before it ends up in a tax return.”

We will check your books

We review your accounting, find the mistakes, correct them and explain how to avoid them in future.

Buhalterinė apskaita · +370 635 87770

Information valid for 2026. The actual consequences depend on the situation.