2026 Information Returns: Which Forms Should Self-Employed Workers and SMEs Watch?

At the start of every year, on top of the regular VAT and withholding filings, self-employed professionals and small businesses face a batch of information returns: forms that don’t involve any payment to the Tax Agency, but that form the backbone of its data-crossing system — the mechanism it uses to spot discrepancies and, when something doesn’t add up, issue formal requests for information. In 2026, this set of forms remains one of the areas where small administrative slip-ups most often turn into entirely avoidable penalties.

Which information returns to watch in 2026

The best known is Form 347, the annual return of transactions with third parties, required whenever total dealings with a single client or supplier exceed €3,005.06 in the calendar year. Alongside it sit Form 190, the annual summary of personal income tax (IRPF) withholdings applied to employees and professionals; Form 180, its equivalent for rental withholdings; Form 390, the annual VAT summary (businesses that file monthly under the Immediate Supply of Information — SII — system are exempt from this one); and Form 349, for businesses carrying out intra-EU transactions.

None of these forms is new, but each filing season brings its own wrinkles: tweaks to the submission formats, adjustments to exemption thresholds, or changes stemming from the gradual rollout of e-invoicing and verifiable invoicing systems (Verifactu), which are reshaping how the underlying information is generated and stored before it ever reaches these returns. The more automated your invoice records are throughout the year, the less reconstruction work you’ll face in January.

What this means for your business

In practice, this calls for some very concrete steps. First, before year-end it’s worth checking which clients and suppliers have crossed the Form 347 threshold, and confirming that the figures your firm is about to report match what the other party will report: a mismatch between what you declare and what your counterpart declares is one of the most common triggers for a subsequent Tax Agency inquiry. Second, if you hire professionals or rent premises, you need to verify that every withholding applied during the year has been correctly recorded and lines up with what was reported quarterly on Forms 111 or 115 — since Forms 190 and 180 are essentially the annual summary of those quarters, any error made along the way carries forward and surfaces in January.

Third, if your business deals with clients or suppliers in other EU countries, Form 349 requires intra-community transactions to be correctly identified from the moment they’re booked, not at year-end — which means checking your client’s VAT number against the Register of Intra-Community Operators (ROI) before you even issue the invoice. And fourth, don’t leave it until the last week of the deadline: even though these returns don’t generate any amount to pay, filing late or with inaccurate data carries fixed penalties, regardless of the fact that there’s no financial loss to the Treasury.

Planning ahead avoids surprises

The most effective way to get through this filing season isn’t to rush in January — it’s to keep your books up to date all year round: invoices recorded in the right quarter, withholdings calculated correctly from the very first payslip or professional invoice, and regular reconciliation between what’s been reported quarterly and what will appear in the annual summary. When your accounting is kept current, information returns stop being a stressful year-end scramble and become nothing more than a straightforward export of data that’s already been checked.

At Zythos Business, this is exactly how we work: reconciling our clients’ books every quarter against what’s actually been reported, so that when it’s time for the information returns, there are no surprises and no mismatches between what your business reports and what your suppliers or clients report. If you’d like us to review how your company stands ahead of this filing season, we’re here to help you go in with your numbers already closed out.