How to communicate monthly invoicing to the AT

What is it for?

Every month, the previous month's invoicing is communicated to the Tax and Customs Authority (AT). fiscaldoo's Monthly communication (SAF-T) brings together, in one record per month, the file, its validation, the list of documents it contains and the proof of submission on the Portal das Finanças. When the record becomes Submitted, the month is shown as “delivered” in the SAF-T summary.

fiscaldoo does not submit the file itself: you submit it on the Portal das Finanças and then record it here.

When to use it?

• At the start of each month, for the previous month, before the deadline.
• When What is there to do with the SAF-T? shows a billing file that is Not generated or not yet delivered.
• To keep the receipt reference of a month already delivered.

Where to find it?

Accounting › Declare › Tax Authority › Monthly invoicing communication

Before you start

• Your profile is Certified Accountant / Fiscal Manager with Fiscal officer. All the steps were done with this profile, up to Submitted.
• The month's documents have been issued and the month's file already generates without errors: How to generate the billing SAF-T file. This article continues that one: the example month is September 2026, with invoices FT D26/28, FT D26/29 and FT D26/30.
• You have access to the company's Portal das Finanças account, to submit the file.

How to use it

1. Open Accounting › Declare › Tax Authority › Monthly invoicing communication. The list has one record per month, with the State, the Documents, the Portal receipt reference and the Submission date.
2. Click New. The Year and Month default to the current month: in Month, choose the month to communicate, for example September. Click Save.
3. Click Generate and validate the file. The record becomes File ready and shows the SAF-T export created, the File validation (Generated), the XSD/integrity errors (0) and the Documents (3).
4. Check the documents: Documents in the file lists the invoices the file contains (in the example, the three from September, €6,452.25 in total including VAT). If an invoice you issued that month is missing, do not submit: see “Common problems”.
5. Click Download file and save the XML.
6. Submit the file on the Portal das Finanças and keep the receipt the Portal returns. Pending on-screen validation: the submission on the Portal das Finanças happens outside fiscaldoo and cannot be done with the demo; the name of the option on the Portal was not seen.
7. Back in the record, under PORTAL RECEIPT, type the Portal receipt reference (in the example REC-DEMO-2026-09, fictitious) and choose the Submission date: the date on the Portal's receipt, not the day you record it here. Receipt (PDF) links the receipt PDF, if you saved it in fiscaldoo. Click Save. If the date is after the month's deadline, a yellow banner says so straight away (see “Expected result”).
8. Click Register the submission. The Confirmation window asks: “Mark every document of the month as communicated? Do this only after submitting the file on the Portal das Finanças.” Click Confirm.

Expected result

• The record becomes Submitted, with Submitted By (your name) and Submitted At (date and time it was recorded in fiscaldoo).
• Note the date in the example: in the demo, September's Submission date is 29/10/2026, after that month's deadline (06/10/2026, see “Important notes”). fiscaldoo accepts it, because it records the submission as it happened, and shows the banner “The submission date (29/10/2026) is after the deadline of this month (06/10/2026): the delivery was late. It is registered as it happened; check with the certified accountant whether the late delivery has consequences.” The banner appears when you save the date (step 7) and stays on the record after Submitted. In a real company, check the date against the deadline before you click Register the submission.
• In Accounting › Declare › SAF-T file › What is there to do with the SAF-T?, the month becomes “Delivered”: “The September 2026 file was delivered.”
• The month's documents are marked as communicated. No journal entry is created.

Important notes

Record it only after submitting

Register the submission marks every document of the month as communicated. Do it only once you have the Portal das Finanças receipt in hand. The monthly communication has a deadline: in the demo, the September 2026 file was due on 6 October 2026. If you are late, talk to your certified accountant. Pending validation by a certified accountant: legal deadline for the monthly communication, the rule when the day falls on a public holiday, and the consequences of being late.

• The SAF-T (PT) export record also has a Record submission button (Certified Accountant / Fiscal Manager profile), which only stores the receipt on that file. Use the monthly communication: it is what changes the SAF-T summary. In the demo, after Submitted, the file's Submission status stayed “Not sent”: do not use that field to find out whether the month was delivered.
• To see month by month what is still to communicate, the deadline and the history of each invoice: How to communicate invoices to the AT and view the history. Communicating invoices one by one, by webservice, requires the AT credentials. Pending validation by a certified accountant: whether communicating by webservice removes the need to submit the monthly file.

Common problems

“The file did not pass the validation…”

• Symptom: after Generate and validate the file, the record stays in Draft, with File validation Invalid, the number of XSD/integrity errors and the warning “The file did not pass the validation: fix the errors listed in the SAF-T export and generate again. … It cannot be submitted until then.” Pending on-screen validation: in today's demo no month produces an invalid file (October 2026, which gave 4 errors, now gives File ready with 0 errors and 9 documents); the warning quoted is what the screen showed on 29/10/2026.
• What to do: open the record's SAF-T export, fix the errors (How to fix SAF-T validation errors) and click Generate and validate the file again.

“Enter the Portal receipt reference and the submission date…”

• Symptom: when you confirm Register the submission: “Enter the Portal receipt reference and the submission date: the documents are only marked as communicated with the proof of the submission.”
• What to do: fill in the two fields from step 7, save and repeat step 8.

An invoice is missing from “Documents in the file”

• What to do: check the invoice's date and status (a draft is not included) and the company. The documents left out of the file are listed in How to generate the billing SAF-T file, “Important notes”.