iFirma logo iFirma automation · runs weekly

Book iFirma purchase invoices from KSeF as costs

Suppliers now send invoices through KSeF, and each one still has to be downloaded and booked as a cost by hand before it counts in your records.

Cotlet does it in your own iFirma account with list_ksef_purchase_invoices, list_contractors and book_ksef_purchase_invoice, called by your AI agent, an n8n workflow or a script.

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Hosted · nothing to install or maintain

Can iFirma do this on its own?

iFirma's API documents four expense endpoints that add a cost document with its KSeF number (checked 14 Oct 2026), but no call downloads invoices from KSeF or books them from the "Faktury z KSeF" list. Automatic download exists in the app under "KSeF ➡ Konfiguracja" and still leaves the booking to you.

How you do it in iFirma today

  1. Go to "Wydatki ➡ Importuj z KSeF lub wgraj plik" and click the "Pobierz nowe faktury" icon.
  2. Enter the start date; it is the seller's issue date, not the date the invoice was sent to KSeF.
  3. In the "Faktury z KSeF" list, check the seller's NIP, KSeF number, issue date and the net and gross amounts for each document.
  4. Click "Zaksięguj" on a VAT invoice or a corrective invoice; advance and final invoices are booked in an order instead.
  5. Booked documents appear in "Wydatki ➡ Lista wydatków". What repeats: the download and the booking click, for every supplier invoice.

How to book iFirma purchase invoices from KSeF as costs

Prompt

List the purchase invoices that arrived in KSeF since last Monday and are not booked yet. Book the ones from suppliers I already have as contractors and show me the rest.
  1. 01

    Download from the last date

    list_ksef_purchase_invoices fetches new documents from the date you give, so a week of invoices is read as one batch. Documents already booked are skipped by iFirma itself.

  2. 02

    Match the seller to your contractors

    Each seller NIP is looked up with list_contractors. A supplier you already have is booked straight away; an unknown one goes to the "for you" list.

  3. 03

    Sort by document type

    VAT and corrective invoices can be booked directly. Advance and final invoices need an order, so the agent lists them instead of booking.

  4. 04

    Book the matches

    book_ksef_purchase_invoice books one document by its KSeF number. By default it waits for your OK, because a booked cost goes into your tax records.

  5. 05

    Report both lists

    You get what was booked with amounts and what is left, so only the odd suppliers need a decision.

What you get back

Example data

New in KSeF since 2026-10-07: 5
Booked 3:
- Harbor Print Ltd, FV 118/2026: net 650.41, gross 800.00 PLN
- Cloud Hosting SA, 2026/10/771: net 81.30, gross 100.00 PLN
- Office Supply Sp. z o.o., 55/10/2026: net 243.90, gross 300.00 PLN
Left for you 2:
- unknown supplier NIP 5252248481, advance invoice
- Lime Courier, final invoice (needs an order)

Other ways to ask

  • Every Monday, list new KSeF purchase invoices and book only those under 500 PLN gross.
  • Show me everything that arrived in KSeF this month grouped by supplier, and book nothing.
  • Book the invoices from Harbor Print Ltd and tell me about any corrective invoices.

What iFirma allows, and what to know first

  • The start date of a KSeF download is the seller's issue date, not the date it was sent to KSeF.
  • A document whose KSeF number is already in tax records or the expense list is not downloaded again.
  • A VAT invoice offers "Zaksięguj" or adding to a collective expense, and a corrective invoice offers "Zaksięguj".
  • Removing a document from the "Faktury z KSeF" list stops it being downloaded again unless the import period covers its issue date.
  • Downloading from KSeF is available in the Księgowość internetowa package and in the faktura plus and darmowa faktura packages.

book_ksef_purchase_invoice asks for your OK by default. To run it weekly without you, switch confirmation off for that tool in your dashboard.

Sources: iFirma Help: Faktury zakupowe z KSeF · iFirma API: wydatki

Call book_ksef_purchase_invoice from a script

curl

curl -X POST https://cotlet.dev/api/v1/ifirma/ksefs/7010003987-20261012-AB12CD34EF56-7A/purchase-invoice \
  -H "Authorization: Bearer $COTLET_API_KEY"

Example response

{
  "ksef_number": "7010003987-20261012-AB12CD34EF56-7A",
  "booked": true,
  "seller_number": "FV 118/2026",
  "gross": 800
}

MCP: add https://cotlet.dev/mcp/v1 with the same key; the call is ifirma_write → book_ksef_purchase_invoice. Example data.

Schedule it in n8n, Make, Zapier or cron

iFirma tools this automation uses

Cotlet iFirma tools used to book iFirma purchase invoices from KSeF as costs
Tool Parameters
list_ksef_purchase_invoices issued_from
list_contractors name, nip, page
book_ksef_purchase_invoice ksef_number
All 14 iFirma tools with descriptions

Frequently asked questions

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