Books that are behind: where to start, and what really costs money.
Procedure and deadlines verified on 21 September 2026.
The delay is almost never the problem. The problem is what is missing to catch up, and the fact that the deadlines kept running while you were not looking.
First, stop the bleeding
Before opening a single folder, you need to know what is running: an unfiled VAT return, an overdue tax return, salaries paid but never declared. Those three generate fines and interest while you are still sorting invoices.
So the right order is not chronological. You deal first with what is bleeding, then you go back in time.
What actually drives the cost
The number of months behind matters far less than people think. What matters is the quality of what exists.
- Complete bank statements: that is the skeleton. With them, everything can be rebuilt, however roughly.
- Receipts for expenses: without them the cost is not deductible, and you pay tax on a profit you never made.
- Payroll records and the statements from the social insurance funds.
- VAT returns already filed, even wrong ones: they set a starting point.
- Access to the software, or at least an export of the entries.
A full year with statements and receipts is rebuilt in a few days. The same year with no receipts takes several weeks and costs, on top of that, the tax on the expenses you can no longer prove.
What being late actually leads to
The consequences are graduated, and they chain together.
- A fine for late filing, which stays modest as long as it is isolated.
- Late-payment interest on the tax and the VAT not paid over, running without interruption.
- An assessment by default when no return arrives: the authority estimates for you, and rarely in your favour.
- For a company, the risk that the annual accounts are not approved in time by the general meeting, which blocks other decisions.
The tipping point is the assessment by default. Before it, you correct. After it, you have to show the estimate is manifestly wrong, within thirty days, with documents. The burden of proof changes sides.
What we do, in order
The method does not vary much from one file to the next.
- A written stocktake: what exists, what is missing, what is running.
- The urgent deadlines dealt with first, including a request for an extension while one is still possible.
- The rebuild from the bank statements, line by line.
- A named list of what you have to find, so you are not searching at random.
- The filings caught up, then whatever will stop it happening again.
That last step is not decoration. A catch-up with no change of method repeats itself, and it costs twice.
How long can it be left to run?
There is no comfortable threshold. What changes everything is the move to an assessment by default: as long as it has not landed, you are correcting; afterwards you are contesting, with a thirty-day deadline and a burden of proof to carry.
Should the authority be told?
Yes, and it goes better with an announced filing date than with silence. A request for an extension filed before the deadline is almost always better received than an explanation given after it.
Can you catch up without receipts?
The movements can be rebuilt from the bank statements, yes. But an expense with no receipt is not deductible: it comes back into the taxable profit. The cost of being late is often exactly that.
And if several financial years are behind?
We work back from the most recent to the oldest, because the opening balances of the last year depend on the one before, but the tax urgency sits on the most recent one. It is counter-intuitive and it is still the right order.
Tell us what you have.
Not what is missing: what you have. We will tell you how long it takes to catch up and what to find first.