FAQ — frequently asked questions

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General information about Atestio and KSeF
Account and login
Connecting to KSeF
Issuing invoices
Purchase invoices and document scanning
Corrections
JPK_V7
KSeF downtime and outages
Customer payments
Plans, limits, and billing
Accounting firms
Security and data privacy
Integrations and export
Support

1. General information about Atestio and KSeF

What is Atestio?

Atestio is a software platform designed for operating within Poland’s National e-Invoicing System (KSeF). It enables you to issue and send invoices and corrections, receive purchase documents, track revenue and expense balances, generate and submit JPK_V7 tax filings, and generate payment links for clients. The system supports both individual businesses (sole proprietorships, companies) and accounting firms managing multiple clients.

Do I have to use KSeF? From when?

Issuing structured invoices via KSeF is mandatory for VAT taxpayers in Poland. The mandate is phased in: from February 1, 2026 for large enterprises (sales exceeding PLN 200M in 2024), and from April 1, 2026 for all remaining taxpayers. Micro-taxpayers (monthly invoice total up to PLN 10,000) may issue non-KSeF invoices until the end of 2026.

Does Atestio replace an accounting firm or a tax advisor?

No. Atestio serves a technical and supporting role. Determining the tax classification of documents remains the user’s responsibility — for tax matters, please consult a certified tax advisor or accounting firm.

Does Atestio handle full accounting (general ledgers, PIT/CIT tax returns)?

No. Atestio handles invoicing, KSeF integration, corrections, and JPK_V7 filings. Data from Atestio can be exported to external accounting software.

Does Atestio work on mobile devices?

Atestio works in a web browser on desktop, tablet, and phone. The dedicated Android app requires Android 11 or newer.

How do I create an account?

Sign up on the login page using your email address and password, or via your Google or Microsoft account. When signing up by email, a 6-digit verification code is sent to your inbox; your account becomes active once you enter it.

What are the password requirements?

At least 10 characters, including an uppercase letter, a lowercase letter, and a number.

No. One email address corresponds to one account. Both sign-in methods are linked automatically.

I forgot my password. What should I do?

On the login screen, click “I don’t remember my password” and enter your email address — we’ll send you a reset link.

Note: if you sign in via Google or Microsoft, your account has no separate password in Atestio.

How do I enable two-factor authentication (2FA)?

Go to Settings → General → Two-factor verification. Choose your method: an authenticator app (recommended: Google Authenticator, Microsoft Authenticator, or Authy) or an email code. Follow the on-screen instructions.

Important: once enabled, save your backup codes somewhere safe — they’re shown only once.

I lost the phone with my authenticator app. How do I log in?

Use one of the backup codes saved when you enabled 2FA (each works once), then reconfigure 2FA on your new device after signing in. If you’ve lost your backup codes, contact us at pomoc@atestio.pl.

Which account type should I choose: “Business” or “Accounting firm”?

“Business” — choose this if you issue invoices in your own name (sole proprietorship) or for the company you represent (this includes limited liability and joint-stock companies too).

“Accounting firm” — choose this if you manage invoices for several separate entities from one account; it unlocks the Clients tab and lets you invite team members.

I run two businesses. Can I manage them from one account?

A Business account covers one company. To manage several entities from one dashboard, use an Accounting firm account instead. Alternatively, each business can have its own account registered under a different email address.

Can I change my account type later?

Yes, under Settings. Changing it affects the available KSeF connection methods and the menu layout.

3. Connecting to KSeF

How do I connect my business to KSeF?

The setup has three steps:

Sign in to KSeF (with a Trusted Profile or a qualified signature) — outside Atestio, directly on the Ministry of Finance’s own system.
Grant permissions to issue and receive invoices.
Start the connection in Atestio (Settings → KSeF).

The permission only needs to be granted once.

What connection methods are available, and which should I pick?

Available methods: Trusted Profile (recommended for sole proprietors), a KSeF certificate (recommended for accounting firms), a KSeF token, and — for accounting firms — a qualified seal. You can change your connection method later without losing data.

Will KSeF tokens stop working?

The Ministry of Finance has announced an eventual move to certificate-only authentication, but the implementing regulation hasn’t been finalized yet. Tokens remain available; you can switch to certificate authentication in Atestio at any time.

Does Atestio know my Trusted Profile password or my certificate key’s passphrase?

No. Signing in with a Trusted Profile happens directly on the government’s own pages. A certificate key’s passphrase is used only once, to verify the key on upload, and is never stored on our servers.

The connection is active, but my purchase-invoice inbox is empty. Why?

Most often, the permission to receive invoices is missing on the KSeF side. Make sure it’s been granted — Atestio needs both the issuing and the receiving permission together.

I see a “No permission” message.

This means the permission was granted for a different NIP than the one entered in Atestio. Check the NIP in your business settings.

Profil Zaufany (Trusted Profile) won’t open.

Trusted Profile opens in a new tab. Your browser may have blocked it — allow pop-ups for Atestio and try again. Also check that the NIP you entered has exactly 10 digits, with no hyphens or spaces.

What’s the difference between an “authentication” certificate and an “offline mode” certificate?

An authentication certificate is used for everyday KSeF sign-in. An offline-mode certificate is used to issue invoices during an emergency offline period, and requires an already-verified authentication certificate for the same NIP.

4. Issuing invoices

How do I issue my first invoice?

Go to My invoices → Issue invoice. Enter the counterparty’s NIP and the rest of their details are pulled from the registry automatically. Fill in the line items (name, quantity, price, VAT rate), the payment due date, and any required annotations (e.g. cash method, reverse charge). Atestio fills in the invoice number, dates, totals, and seller details on its own.

When should I set up my invoice numbering scheme?

Before issuing your first invoice. Numbers on issued documents can’t be changed retroactively, and the numbering must stay continuous and unique within the calendar year.

How long does it take for a KSeF number to be assigned?

Usually a few seconds. If it doesn’t appear within a few minutes, check the status on the document’s card. A document with no KSeF number hasn’t yet been officially accepted by the Ministry of Finance’s system.

What do the invoice statuses mean?

They progress as: Draft → Sent → Accepted (a KSeF number is assigned) or Rejected. The rejection reason is shown in detail once you open the invoice.

My invoice was rejected by KSeF. What now?

Open the invoice, check the exact reason returned by KSeF, correct the fields it points to, and resend the document.

What is a UPO, and where do I find it?

The Official Confirmation of Receipt (UPO) is the official proof that KSeF accepted the invoice. Atestio fetches it automatically and makes it available right on the invoice.

Which document is legally binding — the PDF or the XML?

The XML file (FA(3) structure) registered in KSeF is the legally binding one. The PDF is only a visualization generated for easier reading. If there’s ever a discrepancy, the XML file governs. Both files can be downloaded from the invoice’s card at any time.

How do I get an invoice to my counterparty?

A counterparty who is an active VAT taxpayer receives the invoice via KSeF automatically. You can also download a PDF version from the invoice card and send it separately (e.g. by email).

Can I edit or delete an invoice already sent to KSeF?

No. Once an invoice has a KSeF number, it can only be corrected by issuing a correcting invoice. Fully cancelling a document is only possible while it’s still a draft, before it’s sent to KSeF.

I’m a VAT-exempt seller — how do I issue a rachunek (bill)?

In the “Issue invoice” form, choose “Rachunek” from the document-type dropdown. A rachunek carries no VAT rates, doesn’t go to KSeF, and saving it in Atestio is the same as issuing it.

How do I issue a Pro Forma invoice? Does it go to KSeF?

Turn on the “Pro Forma” toggle in the document form. A Pro Forma isn’t a VAT invoice under the law, so it doesn’t go to KSeF. Once payment is received, you need to convert it into an actual VAT invoice yourself from the document’s card — that doesn’t happen automatically.

Can I issue an invoice in a foreign currency?

Yes. Atestio automatically pulls average exchange rates from the National Bank of Poland (NBP) and converts the VAT amounts into PLN using the rate from the last business day before the tax point date.

Can I set up recurring invoices (e.g. monthly)?

Yes, on paid plans. This is locked on the free plan.

Go to Settings → Customization, where you can add a logo (PNG or JPG, up to 1 MB), extra header text, your own footer, and your business bank account (IBAN). The account number you enter is also checked against the Ministry of Finance’s White List.

5. Purchase invoices and document scanning

Where do purchase invoices in Atestio come from?

Mostly from KSeF. Atestio automatically syncs structured invoices issued to your NIP by other sellers (KSeF inbox → Costs). You can also add non-KSeF documents manually, or by scanning and uploading a file.

How often do invoices sync from KSeF?

On paid plans, syncing happens automatically at set intervals. On the free plan, you need to trigger it manually with the refresh button.

A purchase invoice I received has an error. What can I do?

From the invoice’s card, two options are available: “Request a correction” (sends a formal request to the seller) or “Reject invoice” (the decision is saved permanently in that document’s history).

What file types can I upload for OCR?

Supported formats are: PDF, JPG, PNG, HEIC, TIFF, BMP, DOCX, and XLSX.

What are OCR credits (AI credits)?

Every time a non-KSeF document is processed and read (a scan, a photo, a file import) it uses one AI credit. Your baseline pool depends on your plan and renews every billing month; unused credits from the free pool don’t carry over. You can buy extra credit packs, and those don’t expire. Check your current usage under Settings → General → AI credit usage.

What does “AI credit limit reached” mean?

It means you’ve used your whole credit pool for the current cycle. To keep using the feature, buy a top-up pack or wait for the pool to renew next month. Issuing invoices in Atestio itself never uses these credits.

What’s the “Factoring” tab?

It shows purchase invoices that formally name a third party (a factor) as entitled to receive payment.

6. Corrections

What’s the difference between a correction and cancelling an invoice?

Cancelling a document is only possible before it’s sent to KSeF — in that case it simply disappears from the active record. Once it’s been successfully sent, the only way to make changes is by issuing a correcting invoice; the original document stays in the system permanently as a reference.

The buyer’s NIP on a sent invoice is wrong. How do I fix it?

A correcting invoice can never swap the buyer’s NIP for a different one. If a mistake was made, you need to zero out the original invoice (a zeroing correction) and then issue a brand-new invoice with the correct NIP. An operation already sent to KSeF can’t simply be “undone”.

What can I fix with a correction in Atestio?

Right now, the system supports: correcting prices and quantities, adding or removing line items, editing the seller’s and buyer’s address details (not the NIP), and fully zeroing out an invoice. Changing the VAT rate, updating item descriptions, and editing dates or payment terms are currently in development.

How do I correct several invoices at once?

Use the dedicated “Bulk corrections” wizard in the main menu. The result is shown for each document separately; one document being rejected doesn’t affect the others.

Which period should a correction be reported in?

On the sales side: a correction that reduces the taxable base is generally reported in the period the reduction’s conditions were agreed and met; one that increases it, in the period the reason for the increase arose. On the purchase side, Atestio suggests the right period but holds the document for the taxpayer’s final decision.

7. JPK_V7

What does Atestio fill in JPK_V7 automatically?

The system automatically includes: sales from issued invoices, purchases imported from the KSeF inbox and manually added documents, the right amounts broken down by VAT rate, GTU codes (where assigned to a product), and assignment to the current period. Atestio doesn’t fill in missing GTU codes the user hasn’t set, and doesn’t decide how to treat purchase-side corrections without the taxpayer’s confirmation.

Does Atestio support quarterly filing (JPK_V7K)?

Yes, the platform prepares both JPK_V7M (monthly) and JPK_V7K (quarterly) files.

When is JPK due?

By the 25th day of the month following the reporting period. If the 25th falls on a Saturday or a public holiday, the deadline moves to the next business day.

Why doesn’t Atestio sign JPK for me?

The law requires the qualified signature or the Trusted Profile (ePUAP) signature to be applied personally by the taxpayer. Atestio’s role is to generate a correct XML file. You sign it locally on your own device (using a tool such as Szafir 2.0, PWPW Sign, or proCertum SmartSign) and upload it back into the system. Only then does Atestio verify it and send the signed file to the Ministry of Finance’s gateway.

The XML download link stopped working.

For security, the download link expires automatically 5 minutes after it’s created. Just go back to step 2 of the wizard and generate a new one.

Sending JPK was held up. Why?

There are usually two reasons: no tax office code has been set (add it under Settings → Advanced), or — for accounting firms sending on a client’s behalf — no UPL-1 power of attorney has been registered. Even while sending is held up, you can still prepare and download the draft file.

What are “held corrections”, and how do I release them?

These are correcting invoices Atestio can’t automatically assign to a specific period. To release one, go to the JPK_V7 tab, use “Specify reason”, and say whether the correction stems from an original error or a later event.

Is JPK available on the free plan?

No, full JPK support is only available on paid plans.

8. KSeF downtime and outages

KSeF is down. What happens to my invoice?

Atestio automatically retries sending the document in the background until KSeF accepts it — you don’t need to click anything. The document keeps a status showing the submission is in progress the whole time. Dashboard alerts let you know about any connection issues on the Ministry’s side.

Do I need to use offline mode myself?

The decision to apply the statutory offline mode (under Art. 106nh of the VAT Act) belongs to the taxpayer alone. Atestio keeps you informed about KSeF’s availability to support that decision.

9. Customer payments

How do I send a customer a payment link?

Open the card of an invoice KSeF has accepted and choose “Issue payment link”. We support BLIK, card payments, and instant bank transfers. Copy the generated link and send it to your customer. Once it’s paid, the invoice’s status changes to “Paid” automatically.

How much does a payment link cost?

Atestio adds no markup of its own. The standard fee charged by the payment gateway’s operator is paid by the seller (the invoice’s issuer).

Why can’t I generate a payment link for a split-payment (MPP) invoice?

Split payment requires a bank transfer carrying a dedicated MPP message that separates the net amount from the VAT. That invoice needs to be paid by bank transfer directly, then marked as paid manually in Atestio.

My customer paid by cash or a regular transfer. How do I record that?

Open the invoice’s card, click “Mark as paid”, and enter the date and method of payment.

Does Atestio check a counterparty’s bank account against the White List?

Yes. A counterparty’s VAT status and declared bank account are checked in the background against the Ministry of Finance’s White List.

10. Plans, limits, and billing

What plans are available, and how much do they cost?

We offer plans sized for individual businesses (Start, Pro, Plus, Company) and dedicated B2B plans for accounting firms (Basic, Starter, Growth, Scale, Enterprise). For current pricing, see atestio.pl/pricing.

Do I pay per invoice?

No. Every Atestio plan is flat-rate. We don’t charge extra for individual invoices or for pulling documents in from KSeF.

How many invoices can I issue on the free plan?

The free business plan only limits the total number of finalized documents (invoices and rachunki) issued in a given month. Drafts, Pro Forma documents, and purchase invoices synced from KSeF don’t count toward that limit.

How do I change my plan?

Under Settings → Billing. Moving to a higher plan takes effect right away, with a prorated charge for the days left in your cycle. Moving to a lower plan takes effect at the start of your next billing cycle.

Is there a discount for paying annually?

Yes — paying annually gets you a lower price than paying monthly; the exact terms are shown on the pricing page.

Is there a free trial?

The trial period is 14 days.

Will I lose access to my invoices if I downgrade?

No. You keep access to documents issued in earlier months (PDFs, UPO receipts, archived XML files) regardless of which plan you’re currently on.

Will I get a VAT invoice for my subscription?

Yes. Once your payment is charged, Atestio issues a purchase invoice via KSeF, which you’ll find in your document inbox shortly after.

11. Accounting firms

What roles can accounting-firm team members have?

Owner — the one full-access role; handles billing with Atestio. One per account.
Admin — full operational access, including managing the team and clients.
Standard — day-to-day work, without access to admin settings.
View only — access with no ability to approve submissions.

How do I invite a team member?

From the dashboard (or Settings), go to “Accounting firm team” and choose “Invite team member”. Enter their email address and permission level. The number of available seats depends on your firm’s plan.

A team member has left the firm. How do I revoke their access?

On the team list, find that person and choose “Revoke access”. This is immediate — it ends all of their active sessions and blocks any further sign-in.

How many clients can I manage?

That depends on your accounting-firm plan (e.g. Starter, Growth, Scale). The Enterprise plan offers custom limits negotiated as part of your service agreement.

How do I issue invoices on a client’s behalf?

The client first needs to grant your firm the right permission directly in KSeF. A team member then adds them under the “Clients” tab — the client’s business details can be filled in automatically from the GUS registry, if that’s been allowed under Settings → Advanced.

Can I send JPK on behalf of clients?

Yes, as long as an active UPL-1 power of attorney is registered with the relevant tax office on the client’s side. Without it, sending is held up by the system.

12. Security and data privacy

Where is my data stored?

Data and documents are stored in Amazon Web Services (AWS) data centers in Frankfurt, Germany (EU region), keeping data residency within the European Union.

How is my data protected?

We use enterprise-grade safeguards: encryption at rest (AES, AWS KMS), encryption in transit (TLS), role-based access control (RBAC), automatic audit logging, AWS WAF network protection, and optional two-factor verification (2FA).

Who else processes my data?

A full, transparent list of authorized sub-processors (including AWS for hosting, Microsoft Azure for document OCR, and a licensed payment provider) is available under the Sub-processors page.

How do I export all my data, or delete my account?

Send a formal request to pomoc@atestio.pl. Data-export requests (under GDPR Art. 15) are handled directly by our support team.

Are my documents used to train AI models?

No. Data provided by users — including documents and information entered into the system — is not used to train AI models.

13. Integrations and export

What does Atestio connect to?

Atestio connects directly to government systems and payment partners: KSeF (Ministry of Finance), the JPK filing gateway, Profil Zaufany (Trusted Profile), the GUS/REGON and CEIDG registries, the White List, VIES, NBP exchange rates, and a payment provider.

Can I export invoices to accounting software?

Yes — on the “My invoices” list, choose “Export to ERP” to download your data as a spreadsheet (XLSX) or a CSV file.

Will Atestio connect to my bank?

Automatically matching bank payments to invoices (Open Banking / PSD2) is currently in development and not yet available in production.

14. Support

Will you answer a tax question (e.g. which VAT rate applies)?

No. As a software provider, we help with the technical operation of the platform and its features. Tax classification stays the user’s responsibility — for those questions, please contact a tax advisor or accounting firm.

How do I contact support?

The simplest way is our contact page: atestio.pl/contact, or by email: pomoc@atestio.pl.

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