RETA Contribution Adjustments and Veri*factu: The Taxes Many Self-Employed Workers Didn’t See Coming in 2026

The 2026 tax summer hasn’t been as quiet as many self-employed workers and small businesses expected. While income tax season fades into the rearview mirror, notices are starting to arrive that many hadn’t seen coming: Social Security contribution adjustments under the real-income contribution system, requests tied to electronic invoicing, and reminders of obligations that, while not new, are now being enforced with more rigor. The sense of a “surprise tax” doesn’t really come from some brand-new levy — it’s the buildup of control mechanisms that the Tax Agency and Social Security have been fine-tuning over the past few years.

The most talked-about case is the regularization of RETA (self-employed) contributions. Since the system of contributions based on actual net income was introduced, each self-employed worker picks a provisional bracket at the start of the year, and once the income tax return is filed, Social Security compares that estimate against the real income certified by the Tax Agency. If the final figure comes in above the chosen bracket, a supplementary payment demand follows; if it comes in below, a refund is due. This data cross-check, which runs with a certain lag after the income tax season closes, is what has caused quite a few self-employed workers in recent months to receive charges they weren’t expecting — especially those who had a better year than forecast or underestimated their income when choosing their contribution base. On top of that, the rollout of mandatory electronic invoicing (Veri*factu, and in parallel, the upcoming B2B e-invoicing mandate) is starting to generate penalties for those who haven’t adapted their invoicing systems within the set deadlines, alongside tighter scrutiny of flat-rate taxation (módulos), direct estimation, and certain cash-heavy activities.

What this means for your business

For a self-employed worker or small business, this translates into very concrete decisions worth making now, not when the notice arrives:

Review the contribution bracket you chose for this year in light of how the year is actually going: if revenue is running higher than forecast, adjusting the base sooner rather than later avoids a hefty lump-sum adjustment next year and spreads the cost across monthly payments instead of a single bill. If your invoicing software still doesn’t meet Veri*factu requirements, don’t leave it for the last quarter — migrating systems, training administrative staff, and reviewing invoice templates all take time, and the penalties for non-compliance aren’t symbolic. Keep and organize your income and expense records more carefully than ever, because the automatic cross-checks between the Tax Agency, Social Security, and electronic invoicing systems leave less and less room for the kind of mismatches that used to slip by unnoticed. And if you operate as a company, keep in mind that the Corporate Tax installment payment schedule keeps running regardless of these developments, so cash flow needs to be planned with every front in mind — not just quarterly VAT.

Getting ahead costs less than fixing it later

The common thread running through all these developments is that the Tax Agency and Social Security no longer wait for the annual return to catch discrepancies — data cross-checks are increasingly automatic and near real-time. That narrows the room to sort things out after the fact without surcharges, but it also gives an edge to those who keep their books up to date: the sooner a gap between forecast and reality is spotted, the easier and cheaper it is to fix. The difference between getting hit with a lump-sum Social Security adjustment or an e-invoicing penalty, and avoiding them altogether, usually comes down to simply how often the numbers get reviewed.

At Zythos Business, we support self-employed workers and small businesses with exactly this kind of ongoing monitoring: we regularly review the contribution base against actual revenue, check that invoicing systems comply with current regulations, and stay ahead of the deadlines and payments that affect each business — so no tax development ever arrives as an unpleasant surprise.