If you've ever wondered what documents to send your accountant every month, you're not alone. It is one of the most common friction points at Portuguese SMEs: the start of the month arrives, and nobody is quite sure what to send, in what format, or by when. The result is predictable — incomplete documentation, deadlines at risk, and mistakes that cost money to fix.
The accountant can only work well with what they receive. If what they receive is fragmented or arrives late, the whole chain breaks. This article gives you the concrete list: the documents you cannot skip, how to organise them, and when to send them.
The invoicing documents you can't be missing
Invoicing is the core of any monthly file. It is the basis for the accounting entries and for calculating VAT.
Invoices issued, credit notes and receipts
Every invoice issued the previous month, along with credit notes, debit notes and associated receipts. If the company uses certified invoicing software, the invoicing SAF-T file can replace sending each document manually. Invoice data must be reported to the tax authority by the 5th of the following month, so the accountant needs the data before that date.
Supplier invoices and expense receipts
Every expense invoice for the month: suppliers, rent, telecoms, fuel, outside services. The practical rule is simple — if the document carries VAT or is deductible, the accountant needs to see it, original or scanned. Don't forget the more informal expenses, like tolls and parking, when they're charged to the company. Every missing document is an entry that cannot be made.
Bank statements: which accounts to include, and in what format
Statements are the basis for bank reconciliation, and it is one of the areas where documentation arrives most incomplete.
Which accounts to include
The main account is mandatory, but it is not the only one. Any account that moves company money needs a monthly statement:
- Savings accounts, investments or term deposits with activity that month.
- Company credit cards.
- Digital wallets used for payments.
- Loan accounts or credit lines with activity.
What format to send it in
The preferred format is the full monthly PDF, together with the OFX file when available, since it allows direct import. Some accountants prefer to access online banking directly: check with yours. Statements should cover the full month, with no gaps, and follow right after month-end close.
Payroll documentation and monthly obligations
For companies with employees, this is the area with the most legal deadlines attached, and where mistakes have the most immediate consequences.
Payslips
The payslip must itemise gross pay, income-tax and social-security deductions — 11% of gross pay, borne by the employee — and net pay. It has to be delivered to the employee by the payment date and kept on file. The accountant needs the month's earnings information to make the entries and calculate the employer's charges.
The monthly earnings declaration and social security
The monthly earnings declaration reports pay and income-tax withholdings to the tax authority. The general filing deadline is the 10th of the month after payment. The accountant handles the submission, but needs data from every employee: days worked, absences, overtime and allowances. Also include proof of payment for the previous month's social security contributions.
The full calendar, with the cut-off dates that make this workable, is in the article on the payroll processing calendar.
What's different for sole traders
Self-employed workers on the simplified regime ("recibos verdes") have obligations that differ from a company with organised accounting. Mixing the two up creates avoidable problems, like incorrect VAT treatment or missed filings.
Sole-trader invoices and billing
Send a copy of every invoice issued that month, or the billing export from the Finance Portal. Attach proof of payments received, to cross-check against billing. If you provided services to clients in other EU countries, tell your accountant: you may need to file the EU recapitulative statement, even while exempt from VAT under Article 53.
Deductible expenses and VAT frequency
Invoices and receipts for expenses tied to the activity — office, equipment, telecoms, travel — should be submitted to support the deductions. For annual turnover under €650,000, VAT is filed quarterly; above that, monthly. Frequency determines how often the accountant needs the documents, so it's worth confirming which regime applies.
Deadlines, and what goes wrong when things arrive late
Many firms ask for documentation between the 1st and the 10th of the following month. This window doesn't exist in law as a single fixed number: it comes from the deadlines of the obligations the accountant has to meet — the monthly earnings declaration by the 10th, the invoicing SAF-T submission by the 5th, and the periodic VAT return with its own dates.
When documentation arrives late, the fixed-date obligations are the first to be affected. Failing to deliver accounting-related documents, and delays in processing them, carry fines, which for a company can be doubled. Beyond the direct financial risk, accounting records must be kept for ten years: missing documents are a serious vulnerability in the event of a tax inspection.
How to set up the monthly routine
Knowing what to send is half the work. The other half is having a system that guarantees those documents arrive on time and organised, month after month, without depending on anyone's memory.
A folder structure that's enough
- Invoices issued
- Invoices received — suppliers and expenses
- Bank statements
- Payroll — payslips and social security proof
- Other — contracts, insurance, one-off documents
Cloud-sharing tools work well, as long as they're set up with proper access controls and comply with GDPR. What matters is not the tool: it's consistency. A routine that happens on the same days every time, with the same criteria, is worth more than a sophisticated system used irregularly. The detailed method is in organising documents for your accountant.
In summary
The essentials don't change: invoices issued and received, bank statements for every active account, payroll documentation where there are employees, and — for sole traders — sales invoices and deductible expenses. The specifics vary with the VAT regime and with whether there are intra-EU clients, but the base is always this.
An accountant who receives complete, well-organised documentation works more effectively, makes fewer mistakes, and protects the company far better. If you'd rather stop managing this process by hand, Zelo centralises and organises the monthly documentation before handing it to your accountant, already structured and within deadline.