IBS and CBS are coming. Is your operation ready?
The biggest tax change in decades begins in 2026. B2B e-commerce will be one of the most impacted — and those who don't prepare will operate in the dark during the transition. Mastery already runs dual regime.
From 5 taxes to 2 — but the transition is complex
The reform replaces ICMS, ISS, PIS, COFINS and IPI with two new tax
Mandatory dual regime
During the transition, your operation must calculate taxes under the old regime (ICMS, PIS/COFINS) AND the new one (IBS/CBS) simultaneously. An error in either creates a liability.
Checkout price changes
The tax breakdown on the invoice and at checkout changes. CBS appears separately. The B2B buyer needs to see the correct tax impact on screen — in milliseconds. Legacy systems can't.
New ancillary obligations
Split payment, tax cashback and new ancillary obligations require systems that process rules in real time. Spreadsheets and batch engines can't keep up.
Tax benefits at risk
Many state ICMS benefits will be phased out. Companies that depend on them need to map the impact and recalculate margins before the transition begins.
The year-by-year transition
The transition period was designed to be gradual, but operational complexity is at its peak while the two regimes coexist.
Without Mastery vs. With Mastery
Without preparation
With Mastery
Questions about Tax Reform
When does the Tax Reform start impacting my operation?
In 2026, with the 0.9% CBS test rate. From 2027, the dual regime (IBS + ICMS) takes effect and operational complexity increases significantly. The time to prepare is now.
Can I keep using my current tax system during the transition?
It depends. If your system is batch or asynchronous, it probably won't be able to calculate two regimes in parallel in real time. Legacy tax engines were designed for the current regime — not for coexistence. Mastery was built with a dual regime from the start.
How does Mastery's impact simulation work?
Mastery calculates taxes under current AND new regime (IBS/CBS)
Will my state tax benefits be extinguished?
Gradually, yes. Between 2029 and 2032, ICMS benefits will be reduced in proportion to the tax's phase-out. Mastery maps your current benefits and recalculates the impact at each phase of the transition, so you can replan margins in advance.
What is split payment and how does it affect me?
Split payment is the automatic collection of IBS/CBS at the moment of the financial transaction, without relying on a payment slip. This requires the tax calculation to be correct and integrated with the payment method. Mastery delivers the calculation in real time to feed that flow.
Don't wait until 2027 to discover the impact
Simulate now how IBS and CBS affect your operation. In 30 minutes, we'll show you the complete tax scenario for your B2B e-commerce.
Simulate the Reform's impact →Ready to automate your tax operation?
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