Brazil's Simples Nacional enrollment window closes January 30

The window that only opens once a year

A business already operating that wants to join Brazil's Simples Nacional simplified tax regime can only request it during January, with a final deadline of January 30, 2026. If approved, the change is retroactive to January 1 — as if the business had been on the regime since the start of the year. Outside this window, opting into Simples is only possible when registering a brand-new CNPJ (business ID).

There's no mid-year second chance, except in exceptional situations (like being excluded for exceeding the revenue cap).

Why this hits hardest for late deciders

A business that realizes in March, June, or October that Simples would be cheaper than its current tax regime has to wait until the following January to switch — nearly a full year paying a tax regime that isn't the most advantageous. That wait has a real cost, not just paperwork friction.

What to decide before the 30th

Three things help you avoid missing the deadline: simulate the business's tax cost under Simples Nacional versus its current regime, with your accountant, based on projected 2026 revenue for the full year — not just historical numbers. Then confirm your business activity is among those allowed under Simples, since some activities are excluded regardless of revenue. And, if the decision is to switch, file the request well before the 30th, avoiding any last-minute system issues.

Where Diglion comes in

Diglion helps small businesses organize the tax regime decision in time for the January window, avoiding a full year of paying more tax than necessary.

Sources consulted

• Receita Federal, Opção pelo Simples Nacional e pelo Simei em 2026, retrieved 2026-01-12.