How to Build an Evidence File for a Dispute with a Polish Company

You bought a service, you paid for it, and the company didn't do what it promised. Or you bought goods and they turned out to be faulty. Now you'd like your money back — through a complaint, or if that doesn't work, through the courts. But what exactly do you need to hand over to prove that this particular company owes you? This guide walks through, step by step, how to gather and organise your evidence — no need to panic, but you do need real attention to detail. A poorly organised set of correspondence can be the difference between winning and a judge asking, "And where is all of this?"

This guide is general legal information, not legal advice. How the rules apply depends on the contract, the evidence and the circumstances, and on whether the case is a consumer, civil, or business (B2B) matter. If you need advice or representation, the matter should be assessed by a qualified Polish lawyer or another appropriate specialist. Twoja Sprawa helps you organise the documents for that assessment.

Evidence — four main categories

Before you start gathering, it helps to understand how proving a claim actually works. In a dispute over money or the exchange of goods, evidence falls into four categories:

1. Contract documents — exactly what you agreed to and on what terms.
2. Proof of payment — that you actually transferred money, and how much.
3. Evidence of non-performance / defects — that the company didn't do what it promised, or that the goods are faulty.
4. Communications — the emails, texts and messages in which both sides discuss the problem.

The fewer gaps you have in each of these four categories, the stronger your position.

What counts as a "contract"?

A contract doesn't need to be a signed piece of paper. It can be:

• The contract document itself — the terms and conditions, price list, or service terms handed to you or published on the company's website (save screenshots of the URL).
• Email — the exchange in which you place an order and the company confirms it.
• Texts / messages — a conversation in which you both agreed what was to be done, for how much, and by when.
• Receipt / invoice — a sales document that itself sets out the main terms.
• A screenshot from a platform — if you ordered through an app or marketplace, screenshot every stage of the order, including confirmations and the terms and conditions.

Straight after the contract is made (ideally the same day): - Print or screenshot the whole contract, including the terms and conditions. - Screenshot the URL where the contract appears (this proves it existed there at that moment). - Print the confirmation email, headers included (date, time, sender, recipient).

Proof of payment

A company can claim all sorts of things, but the moment you pay, you leave a trail. Gather:

• Bank statements or a screenshot from your banking app — showing the transaction with the date, amount, reference number and recipient. If possible, download the full transaction as a PDF from your bank, not just a screenshot.
• Payment confirmation — if your bank sent you a text or email with a reference number, keep it.
• The transaction reference number — in Polish banking this is called the UOP (unikalny numer operacji, "unique operation number"); it appears in the banking system on both sides and is a key link in the chain of payment evidence.
• Receipt / invoice — if you received one at the point of payment, keep it.
• Card payment slip (from a terminal) — the printed transaction receipt.
• Email confirming receipt of funds — if the company sends these.

Important: don't throw away bank statements or confirmation messages. These are exactly what a court will want to see.

Evidence of defects or non-performance

This is the most important part, because it shows the company failed to deliver on the contract. Gather:

For a service not performed, or performed badly:

• Evidence of the state of things — dated photos and video (make sure your camera's or phone's date stamp is switched on; you can also add the date to the file name) showing the problem — an unfinished flat, a repair that never happened, goods not delivered. Don't edit videos or retouch photos — authenticity is everything.
• A specialist's assessment — for a technical problem, an opinion from a surveyor, mechanic, electrician or doctor makes it much harder for the company to deny the defect.
• Insurance policy / warranty — if you bought with a warranty, keep the warranty card and its terms.
• Comparable pricing — prices for identical services from competitors; this sometimes helps show the company overcharged or promised something exceptional.

For faulty goods:

• Photos of the defect — clear, close-up. Colour, dirt, defects, missing parts. For packaging, capture the date and batch/lot number. For electronics, whether it powers on or not, and whether it works.
• A description of the defect (e.g. "The phone doesn't turn on", "The fabric started peeling after three washes", "The print doesn't come out"), noted separately or in a dedicated document.
• Testing the item — if you can show the goods don't meet the stated standard (e.g. a pressure gauge shows the wrong readings, a lamp doesn't reach full brightness), that's evidence in itself. But don't destroy the item without a surveyor's report first — you may need an expert opinion later in the dispute.
• Email or call to the manufacturer — if you reported the defect to the manufacturer and they confirmed it, that strengthens your position.

Communications — the bread and butter of evidence

Every email, text, WhatsApp or Messenger message can be evidence. Keep everything. In particular:

• Emails with the company — print the entire thread from the very first message, headers included (date, from, to, cc). Don't just take a screenshot — save it as a PDF from your browser or directly from your email client (File → Print → Save as PDF).
• Text messages — a screenshot of the whole conversation, with dates visible.
• WhatsApp, Messenger, Telegram — a screenshot of the whole conversation (scroll to the top so nothing is missing). Better still: export it as a PDF or email it to yourself (many apps have this feature built in).
• Chats on e-commerce platforms — if you corresponded through Allegro, OLX or another marketplace's messaging panel, screenshot the whole thread.
• Phone calls — if you spoke on the phone and it mattered, send a follow-up email to the company: "I'm confirming we spoke today about..., and agreed that... Please confirm this in writing." That creates a written record.

Why does this matter? Messages show: - When the problem first arose. - Whether the company acknowledged it or denied it. - Whether it promised to fix things, and by when. - Whether it ignored your follow-ups.

These messages are often more important than the contract itself, because they show how the dispute actually unfolded.

Delivery notes and proof of shipment

If goods were supposed to be delivered:

• The consignment note (courier slip, parcel-locker receipt, etc.) — proof the parcel actually arrived.
• Proof of collection — whether the courier obtained a signature, or the company sent a text saying the parcel was ready for collection.
• Non-delivery notice — if the parcel never arrived, any notice from the courier company.
• A delivery photo (if the courier took one) — some couriers photograph the parcel at the door as proof of delivery.

Timeline — the key dates

Put together a timeline table for your case:

A table like this immediately shows a judge or arbitrator the sequence of events — and that you acted methodically throughout.

Organising your file — from A to Z

Folder structure:

CASE_COMPANY_XYZ_2026/
├── 01_CONTRACT
│ ├── Contract.pdf
│ ├── Terms_and_conditions.pdf
│ ├── URL_screenshot.png
│ └── Order_confirmation_email.pdf
├── 02_PROOF_OF_PAYMENT
│ ├── Bank_statement.pdf
│ ├── Reference_number_12345678.txt
│ └── SMS_confirmation.png
├── 03_COMMUNICATIONS
│ ├── Email_thread_1_from_2026-01-10.pdf
│ ├── WhatsApp_conversation_2026-02-01.pdf
│ ├── SMS_history.png
│ └── Phone_call_followup.pdf (your follow-up confirmation email)
├── 04_EVIDENCE_OF_DEFECT_NONPERFORMANCE
│ ├── Defect_photo_1.jpg (dated in the file name)
│ ├── Defect_photo_2.jpg
│ ├── Problem_video.mp4
│ ├── Surveyor_report.pdf
│ └── Test_results.pdf
├── 05_ADDITIONAL_DOCUMENTS
│ ├── Manufacturer_warranty.pdf
│ ├── Insurance_policy.pdf
│ └── Competitor_prices.xlsx
└── 00_INDEX.txt (list of all files with notes)

Index file (00_INDEX.txt) — format:

CASE: Dispute with Company XYZ sp. z o.o. (Polish limited-liability company)
DATE: 26 Jun 2026
SUBJECT: Building service not performed / faulty goods

CATEGORY 1: CONTRACT
- 01_CONTRACT/Contract.pdf (date: 10 Jan 2026, pages 1-5)
- 01_CONTRACT/Terms_and_conditions.pdf (date: 10 Jan 2026)
[...]

CATEGORY 2: PROOF OF PAYMENT
- 02_PROOF_OF_PAYMENT/Bank_statement.pdf (transaction 15 Jan 2026, amount 5,000 PLN, ref. 123456)
[...]

CATEGORY 3: COMMUNICATIONS
- 03_COMMUNICATIONS/Email_thread_1.pdf (period: 10 Jan – 15 Apr 2026; 12 emails)
 * Email of 10 Feb 2026: I ask for a status update, the company admits the delay.
 * Email of 1 Apr 2026: I report the goods as faulty, the company disputes this.
[...]

Why bother with an index? Because once you have 50+ documents, whoever reviews the file — a judge, an arbitrator — will appreciate knowing straight away what's where. It signals that you're organised and credible.

Mistakes to avoid

• Editing or retouching photos — if evidence isn't authentic, a court will spot it. Always use clean, unretouched photos.
• Missing dates on photos — cameras have a built-in clock; check it's switched on (EXIF data).
• Deleting old messages — "I don't have that text anymore" is a weak excuse. Apps like WhatsApp have an export function — use it straight away.
• Missing email headers — a printout of the body text alone, without date and sender, isn't very credible. A PDF exported from your browser is better than a screenshot.
• Too many originals in circulation — always keep copies; don't hand over your only original to the court.
• No single point of contact — if you dealt with five different people at the company, arrange all those conversations in chronological order so it's obvious you kept chasing consistently.

What you can claim — in general terms

At the evidence-gathering stage, don't try to work out exact compensation amounts (that's for the court or arbitrator to assess), but bear in mind you may be able to claim:

• a refund of the price paid (if the goods or service were never delivered at all),
• a price reduction (if the service was carried out, but poorly),
• reimbursement of repair costs (if you fixed the defect yourself at the company's expense),
• compensation for inconvenience (in some consumer cases).

When a case is worth taking to a lawyer

Your evidence file should always be reviewed by a specialist when:

• the amount involved exceeds 10,000 PLN,
• the dispute has been running for more than three months,
• the company actively denies everything, with no realistic prospect of an amicable resolution,
• you need to act quickly because a limitation period is approaching.

When a case may not be economically worth pursuing

Before you build the whole file, think about whether it's actually worth it:

• A small amount (under 1,000 PLN) combined with a complicated case — the cost of pursuing it may outweigh what you'd recover.
• No clear contract (everything verbal, no texts) — it will be hard to prove exactly what was agreed.
• No way to identify the company (no clear name, unstable contact details) — a court has no one to serve proceedings on.

Common mistakes people make

• Only starting to gather evidence after the problem has already dragged on — by then it's lost its freshness and consistency.
• Mixing facts with emotion — "this company is a bunch of crooks and everyone knows it" isn't evidence; "on date X the company failed to do Y" is.
• Keeping no copies — "I have the original, but only the one copy" is a real risk. A PDF copy of every document is the bare minimum.
• Ignoring time limits — if you wait two years to complain when the rules give you 30 days, that's a problem. Gather your evidence quickly.

Frequently asked questions

Is a text message admissible as evidence in a Polish court? Yes, but it needs to be credible and consistent with the other evidence. A screenshot of the whole conversation is much stronger than a single message taken out of context.

Can I just print an email from Gmail or Outlook and call it evidence? It's better to export the email as a PDF (with headers) or get a confirmation directly from your mail server. A screenshot can work too, but a PDF exported from your browser is more credible.

What if the company is based abroad? The evidence you need to gather is the same, but you'll also need to work out where to bring the claim (jurisdiction). That's a question for a lawyer — but the evidence itself matters just as much either way.

Do I need a surveyor's or expert's report? It depends on the case. For a technical defect — usually yes, an expert opinion strengthens your position considerably. For a straightforward payment dispute — not always. A lawyer can tell you whether it's necessary.

How much time do I have to gather evidence? As soon as possible after the problem arises. People forget details, change phones, and lose messages. The fresher the evidence, the stronger it is.

Can I just say "I have more evidence, but I don't have it with me right now"? You can, but it looks weak. Submit the whole file to the court in one go.

Last verified: 26 June 2026.

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