Brazil Delays Testing of Single-Phase Tax on Goods and Services (IBS) /Contribution on Goods and Services (CBS) Rules

Brazil’s Technical Note 2025.002 (v1.35) postpones the validation of IBS/CBS single-phase taxation rules in the testing environment, meaning these rules are not currently enforced. While this gives authorities more time to refine the system, it delays full testing for businesses and requires adjustments to implementation timelines ahead of the 2027 mandate.

Brazil has released version 1.35 of Technical Note 2025.002 for e-Invoices (NF-e) and digital receipts (NFC-e), introducing an important change for businesses and software providers.

The update postpones the application of validation rules related to single-phase taxation under Tax on Goods and Services (IBS) and Contribution on Goods and Services (CBS) in the testing (homologation) environment.

The new version adds a note indicating that certain validation rules are planned for future implementation, meaning they will not currently be enforced during testing.

As a result:

1. Systems cannot fully test single-phase taxation scenarios at this stage,
2. Several validation rules that would normally trigger rejections are temporarily inactive.

This change directly affects ongoing implementation projects:

1. Testing of IBS/CBS single-phase scenarios is delayed,
2. Companies must adjust timelines and testing strategies,
3. Full technical validation will only be possible once the rules are reintroduced.

The testing environment update is scheduled for April 6, 2026, but the single-phase taxation regime itself will only become mandatory in 2027.

This suggests that tax authorities will continue refining the rules during 2026, with the expectation that:

1. Validation rules will be reintroduced later in 2026,
2. Businesses will still have time for proper testing before going live.

The update temporarily pauses validation of single-phase IBS/CBS rules in testing, giving authorities more time to finalize the system, but requiring businesses to replan their implementation and testing activities.