Reconstruction of accounting records – when you must do it and how to do it efficiently
18 Feb 2026
Loss, destruction or missing accounting documents is one of the most common “dark hours” for a business owner. Office flood, disk failure, tax audit, a previous accountant’s mistake or documents that simply “went missing” – causes vary. You cannot just “put something in Excel”. You must legally reconstruct accounting records so they meet the Accounting Act and the Tax Ordinance.
Below we explain what reconstruction means, when it is mandatory and what an effective process looks like.
What is reconstruction of accounting records?
It is the official process of rebuilding full accounting documentation (general ledger, tax ledgers, VAT, fixed assets, ZUS settlements, etc.) from available source evidence when originals are lost or illegible.
In practice this means:
- Collecting and organising all available traces of transactions.
- Supplementing missing evidence (invoice duplicates, bank statements, transfer confirmations, contracts, minutes).
- Preparing missing accounting entries.
- Preparing declaration corrections (VAT, PIT, CIT, JPK_V7).
- Achieving compliance so a tax audit finds no objections.
When is reconstruction necessary?
Typical situations where you cannot delay fixing documentation:
- Force majeure: flood, fire, theft of documents or servers.
- Technical problems: accounting system failure without a current backup.
- Legal context: tax or ZUS audit revealing gaps.
- Human error: ending cooperation with an unreliable accounting office or errors by a previous accountant.
- Strategic changes: sale of the company, investor entry or change of tax form requiring recalculation.
Ways to reconstruct – alone or with professionals?
Option 1 – on your own (rarely recommended)
You can try if the gap is small (a few months) and you have all bank statements. The downside is huge time consumption, error risk and fiscal criminal liability for incorrect books.
Option 2 – professional accounting office (recommended in 95% of cases)
An experienced team can rebuild full books in a few to several weeks, file declaration corrections and prepare documentation for a possible audit.
Our reconstruction process
Our process is transparent and aimed at maximum relief for the entrepreneur:
- Free diagnosis: We analyse what is missing and what can be recovered.
- Gathering evidence: We help obtain invoice duplicates, ZUS data and e-declarations.
- Rebuilding entries: We prepare missing books month by month.
- Declaration corrections: We file necessary VAT, CIT/PIT and JPK corrections.
- Representation: If needed, we correspond with the tax office and ZUS.
- Finalisation: We hand over “clean” books compatible with popular systems (Symfonia, Comarch, Insert).
How long and how much does it cost?
| Company size | Duration | Notes |
| Small company (up to 100 docs/month) | 6–12 weeks | Depends on speed of obtaining duplicates |
| Medium and large | 12–18 weeks | Full quote after free analysis |
Our recommendation
If you are missing more than 2–3 months of books – do not take risks. A penalty for improper bookkeeping can reach 240 daily rates (in 2026, in extreme cases amounts in the millions of PLN). Better to do it once, thoroughly and with peace of mind.