Accounting firms
All your clients' invoices in one workspace, each client kept separate. You see at once what is already in KSeF and what is waiting for a fix.
See the firm's workspaceHundreds of invoices
to KSeF.
One file.
A whole month in one Excel or CSV file, or many PDF and XML files at once. FakturaFlow builds the FA(3) XML (the KSeF invoice format), checks the required fields and sends everything to KSeF, Poland's National e-Invoicing System. It collects each UPO (official KSeF receipt) by itself.
14 days of full accessXML validator, no account (in Polish)
One file for the whole month
An Excel or CSV file with the whole month. Or straight from Stripe, Chargebee or Xero.
You know what to fix
Instead of a KSeF error code, you see which field to fix and what to enter in it.
UPO without the chasing
The UPO for every invoice is collected automatically.
Who it's for
Three kinds of company.
The same pile of invoices.
You do not need to know the FA(3) schema. You see the invoice the way you know it, and FakturaFlow takes care of the rest.
Companies with their own sales system
Do you issue hundreds of invoices a month in a sales or billing system, perhaps your group's ERP? Export an Excel or CSV file, upload it once and send everything.
How it works for foreign groups
Subscription businesses
Connect Stripe, Chargebee or Xero. Invoices from those systems appear in FakturaFlow by themselves. Send them with one click, or automatically.
See the integrations
Every accepted invoice gets a KSeF number.
KSeF gives each accepted invoice a number and issues the UPO, the official receipt. FakturaFlow saves both with the invoice, so you know what was accepted.
- Invoice
- FV/2026/10/0028
- KSeF number
- 1234563218-20261002-7A3F09C21E4B-5D
- Status
- SentUPO received 02/10/2026, 14:32
Sample data
Check your XML file without an account (in Polish)How it works
Upload a file.
Fix what needs fixing.
Send it all.
On the Professional plan and above you do not send invoices one by one. You upload the month, fix what FakturaFlow flagged, and send the rest with one click.
Upload your files.
One Excel or CSV file for the whole month, or many PDF and XML files at once.
Check the flagged fields.
For every error you see what is wrong and what to do about it.
Send in bulk.
Up to 500 invoices in about 10 minutes. The time depends on KSeF load. UPOs are collected in the background.
Sending needs a KSeF token or certificate of the company that issues the invoices. You generate the token in the Ministry of Finance's KSeF Taxpayer App (Aplikacja Podatnika KSeF).
InvoicesDemo firmSample data
This month47Ready6
Lipa Hurt Sp. z o.o.Client: Olszyna Meble
FV/2026/10/0028PLN 12,430.00SentPracownia Wrzos s.c.Client: Olszyna Meble
FV/2026/10/0027PLN 3,200.00KSeF errorBuyer NIP missing
The invoice has no buyer NIP (Polish tax ID).
Add the buyer's NIP in the invoice details (the “Buyer” tab) or fix the source file.
FixVerify
Kawiarnia Pod LipąClient: Dom Kawy Ziarno
FV/2026/10/0019PLN 1,890.00Needs fixingHotel Sosnowy Sp. j.Client: Dom Kawy Ziarno
FV/2026/10/0018PLN 8,750.00ReadyZielony Dach S.A.Client: Olszyna Meble
FV/2026/10/0026PLN 21,100.00Sent6 invoices ready to sendSend all
Sample data. Company names and NIPs are fictitious.
The whole month, hard invoices included.
Invoices to foreign buyers and in foreign currencies take the same route as an ordinary invoice: you upload, check, send. You issue a correction with the Correct button next to a sent invoice.
- Correction invoices (KOR)
- Foreign buyers
- Invoices in foreign currencies
- Split payment (MPP)
- Invoices for local government units (JST)
- Purchase invoices from KSeF
Do you issue invoices in Stripe, Chargebee or Xero?
Connect your account once. New invoices appear in FakturaFlow by themselves. Send them with one click, or switch on automatic sending.
IntegrationsDemo firmSample data
StripeLast fetch: 02/10/2026, 14:20
ConnectedChargebeeLast fetch: 02/10/2026, 13:58
ConnectedXeroSales invoices from a Xero organisation
ConnectSend to KSeF automaticallyOff by default. Then you send with one click.
OffThe connection needs access to your account in that system. Integrations are available on the Integration plan.
Check a file before you sign up.
Two free tools. Up to 3 uses a day without an account. Both are in Polish.
XML validator
Paste XML or upload an FA(3) file and see what needs fixing before you send it to KSeF.
Open the validator (in Polish)PDF to XML converter
Turn a PDF invoice into an FA(3) file. You fix the fields in the preview before you download the XML.
Open the converter (in Polish)Customer
„Wystawiamy 400 do 600 faktur miesięcznie w zewnętrznym systemie i potrzebowaliśmy sposobu, żeby wysyłać je do KSeF hurtowo, bez ręcznego przepisywania. FakturaFlow bierze nasz plik i wysyła wszystko za jednym razem, razem z UPO. Kiedy trafiliśmy na błędy, poprawki wchodziły tego samego dnia. System jest bardzo sprawny, a obsługa klienta na najwyższym poziomie!”
English translation“We issue 400 to 600 invoices a month in an external system and we needed a way to send them to KSeF in bulk, without retyping them by hand. FakturaFlow takes our file and sends everything in one go, together with the UPO. When we ran into errors, the fixes came the same day. The system is very efficient and the customer service is at the highest level!”
Pricing
From PLN 199 a month.
Every new account gets 14 days of the full Professional plan free, no card. After the trial you choose the plan that suits you. Your data stays after the trial too.
Starter
PLN 199/ month
up to 10 clients
1 user (owner only)
- Upload PDF, Excel, CSV and XML
- PDF to FA(3) XML conversion
- Sending to KSeF
- No monthly invoice limit
- KSeF errors with fix instructions
- Full history and UPO downloads
Professional
Most popularPLN 319/ month
up to 30 clients
up to 5 users
Everything in Starter, plus:
- Bulk sending (many invoices at once)
- Team invitations
- Priority support
Enterprise
PLN 499/ month
unlimited clients
unlimited users
Everything in Professional, plus:
- Help with setup and the first import
- A named account contact (by e-mail)
Integration plan
Do you have your own invoicing system?
If your invoices are already created in Stripe, Chargebee or Xero, you do not have to move anything. We connect to your system, check every invoice and send it to KSeF, and collect the UPO automatically. You set up the connection yourself in a few minutes, or we do it for you. Another invoicing system? You can upload a CSV or Excel export right away, and we can add a direct connection. Tell us which system.
Bulk sending from the Professional plan. Stripe, Chargebee and Xero on the Integration plan. During the trial you have access to everything.
Frequently asked questions
What to know before you try it.
The questions we hear most from accountants and firm owners considering FakturaFlow. Missing something? Write to us.
The Ministry's app is great for one company: you issue an invoice, click, done. We designed FakturaFlow for accounting firms that serve dozens or hundreds of clients, and it works just as well for one company with a large monthly volume. Bulk upload of PDF, Excel and XML files, FA(3) validation of the whole batch at once, a UPO archive split by client, one login instead of a separate one for each NIP. For a small company the Ministry's app is enough. For a firm it does not scale.
No. FakturaFlow works alongside your accounting system, not instead of it. It takes over the FA(3) validation and the communication with KSeF: importing invoices from different sources, schema validation, bulk sending and collecting UPOs. All bookkeeping, JPK files (Poland's standard audit files) and VAT returns stay in your Optima, Symfonia or InsERT.
No. Clients stay in their own systems. FakturaFlow accepts data in the form you receive it (PDF, Excel, CSV, XML) and prepares it for KSeF. Your client records in your main accounting software are not touched.
Yes. That is how KSeF is built, whatever the tool. Each client generates a token in the KSeF Taxpayer App (Aplikacja Podatnika KSeF) and passes it to the firm. FakturaFlow stores tokens on encrypted disks (AES-256) and uses the right one for each send. Once saved, a token can no longer be read by the browser; only the server uses it. According to the Ministry of Finance's announcement, tokens issued until 31 December 2026 are to work until 30 November 2027, and new tokens always have an expiry date. FakturaFlow also supports logging in with a KSeF certificate.
After every send KSeF returns a UPO (Urzędowe Poświadczenie Odbioru), the official receipt: an XML file that serves as legal proof the invoice was delivered. FakturaFlow collects the UPO automatically, saves it in the client's archive and lets you download it at any time. On the Professional and Enterprise plans there is also a bulk export to ZIP.
Servers in Europe (London), AES-256 encrypted disks and TLS 1.3 in transit. Each firm's data is separated from other firms at database level, and within a team the owner or an account administrator manages clients and payments. A full data processing agreement (GDPR Art. 28) is available on request before you start. The validator and the PDF to XML converter run 100% locally. Files do not leave your browser.
Yes. The FA(3) XML validator and the PDF to XML converter work without logging in: full functionality, 3 uses a day for free. Both tools are in Polish. Once you create an account you get 14 days of the Professional plan free, without entering a credit card.
Yes. Use the PL | EN switch at the top of the page; the app follows your choice. Our e-mails are still in Polish, and KSeF's own messages arrive in Polish when we have no translation for them. Support is by email, in English, Polish or Swedish.
A whole month of invoices in KSeF in one go.
14 days of full access. The XML validator works without an account (in Polish).