What changes in the tax reform in 2027?

In 2027, PIS and Cofins are abolished, and CBS starts being collected. IPI goes to zero, except for products from the Manaus Free Trade Zone, and the Selective Tax begins, according to the Receita Federal page updated on October 16, 2026.

Is an invoice without IBS and CBS rejected?

For companies under the regular regime, yes. According to the IBS Management Committee, since August 3, 2026 an electronic tax document without the IBS and CBS fields is no longer authorized. Simples Nacional companies start showing both taxes only from 2027.

Does a company pay IBS and CBS in 2026?

The invoice shows 0.9% CBS and 0.1% IBS. According to Receita Federal, those who meet the ancillary obligations are exempt from paying that amount in 2026, which is a test year.

What is the deadline for Simples Nacional companies to opt for IBS and CBS outside the DAS?

Resolução CGSN 194/2026 extended the option for the regular IBS and CBS regime for 2027 to October 30, 2026. The option can be withdrawn from November 3 to December 20, 2026, according to CRC-SP.

Can an accounting firm charge more because of the tax reform?

It can, if the contract provides for it. Resolução CFC 1.590/2020 requires a written contract with the fee for each service, the adjustment rules and provision for amendments. Work not covered by the contract becomes a separate service.

Tax reform at the accounting firm: what changes in 2026 and 2027 and how to get the new work into your fees

By Victor Ferreira · October 26, 2026 · 7 min read

In 2026, IBS and CBS are in a test phase: the invoice shows 1%, and those who meet the ancillary obligations don't pay it. In 2027, CBS replaces PIS and Cofins. For the accounting firm, this means new work per client, and work not covered by the contract becomes a separate service.

What changes in the tax reform in 2026 and 2027?

In 2026, the new taxes appear on the invoice as a test. In 2027, CBS starts being collected, and PIS and Cofins cease to exist. This is the timeline from the Receita Federal page, updated October 16, 2026:

Year	What happens
2026	Test year: 0.9% CBS and 0.1% IBS, offset against PIS and Cofins. Those who meet the ancillary obligations are exempt from paying
2027 and 2028	PIS and Cofins abolished. CBS collected, IBS at 0.1%. IPI at zero, except in the Manaus Free Trade Zone. The Selective Tax begins
2029	IBS at 10%; ICMS and ISS at 90%
2030	IBS at 20%; ICMS and ISS at 80%
2031	IBS at 30%; ICMS and ISS at 70%
2032	IBS at 40%; ICMS and ISS at 60%
2033	End of ICMS and ISS; the new model applies in full

The tax calculation stays in the firm's accounting system. What grows is the conversation with each client: registration data, tax regime, rejected invoices and the 2027 math.

And the conversation has already started. The Sondagem Omie do Setor Contábil, carried out with Fenacon and the Sescons, came out in Contábeis in July 2026. In it, 68% of 633 firm owners had already been approached by clients about the reform. Another 56% are still studying the topic, with no structured action plan.

What has already changed on invoices since August 2026?

For companies under the regular regime, an invoice without the IBS and CBS fields is no longer authorized. According to the IBS Management Committee, in a statement of June 15, 2026, the rule has applied since August 3. The document must show the 1% test rate, of which 0.9% is CBS and 0.1% is IBS.

Three points generate most of the questions:

Simples Nacional. In 2026, nothing changes for Simples companies. According to the Management Committee, they start showing IBS and CBS from 2027.
NFS-e. In early 2026, showing the taxes on the service invoice was optional. Confirm the rule in each client's municipality.
Penalties. The Management Committee and Receita Federal announced a period with no penalties for good-faith errors at the start of the transition. That doesn't prevent the invoice from being rejected.

In practice, the rejection reaches the firm through the client's WhatsApp, with a screenshot from the invoicing tool. Without a record per client, the same question comes back the next month.

What new work does the reform bring for each client?

The reform doesn't move the tax calculation. It adds tasks per client, and each one has a deadline. This is an example list to build the firm's checklist:

Task	Who needs it	When
Review the product and service registry for the IBS and CBS fields	Clients under the regular regime	Before the next rejected invoice
Check the client's invoicing tool	Everyone who issues invoices	At the first rejection
Simulate Simples with IBS and CBS inside or outside the DAS	Simples companies that sell to businesses	By October 30, 2026 for 2027
Explain the end of PIS and Cofins and the 2027 CBS	Regular regime	By December 2026
Review prices and contracts with suppliers and customers	Those with long-term contracts	Throughout 2027
Answer questions in writing and keep the answer	Everyone	Always

The Simples deadline matters now. Resolução CGSN 194/2026, of September 28, extended to October 30, 2026 the option for the regular IBS and CBS regime. The option can be withdrawn from November 3 to December 20, according to CRC-SP. The choice applies from January 1, 2027.

Those who buy from a Simples company may want the IBS and CBS credit. That is why the simulation depends on who your client's customers are. It is a calculation that changes from company to company and takes the analyst's time.

Can the firm charge for the reform work?

It can, if the contract gives it a basis. Resolução CFC 1.590/2020 requires a written contract (art. 2). It describes the services, the fee for each one, the adjustment rules and provision for amendments. What isn't described in the contract can become a separate service.

The problem is that the sector tends to put everything in the monthly fee. In the Sescon-SP study with Omie, published by Fenacon on October 15, 2026, 73% of 314 firms charge a fixed monthly fee. And 63% include ancillary obligations in the fee, with no separate charge.

The same study shows the sector split on raising prices:

34% see the reform as a chance to charge more for advisory work;
27% plan to review the price of recurring services;
16% say clients understand little about the reform, and that makes a price increase harder;
50% name pressure for low prices as the biggest pricing difficulty.

The expectation of higher prices already existed. In the IOB survey with Folha, published in September 2025, 53% of accountants expected the price of accounting services to rise with the reform.

How do you get the reform work into your fees?

Measure the work per client before proposing a price. Clients accept a price better when it comes with the list of what was done. This is a step-by-step:

Separate the reform from routine work. Create a compliance checklist per client, outside the month-end close.
Count what each client asked for. Questions answered, rejected invoices reviewed and simulations done in the month.
Define the package. For example: a one-time registry update, a Simples simulation and monthly follow-up in 2027.
Write the amendment. Describe the service, the price and the term, as Resolução CFC 1.590/2020 requires.
Show the history. In the price adjustment conversation, the client's list of requests backs up the number.

The table below uses example numbers for a firm with 40 clients under the regular regime:

Item (example)	Per client	40 clients
Registry and invoicing tool review, one time	3 hours	120 hours
Rejected invoices reviewed per month	1 hour	40 hours per month
Questions answered per month	0.5 hour	20 hours per month

That is 120 hours of compliance work and 60 hours per month of follow-up. If this goes into the old monthly fee, the firm pays for the client's reform.

One point in the firm's favor: art. 127 of LC 214/2025 cuts IBS and CBS on accountants' services by 30%. For a legal entity, the reduction has requirements, such as all partners being licensed and the service being provided by them. Check how your own firm qualifies.

How CERNE solves it

CERNE works alongside the accounting system. Bookkeeping and tax calculation stay there. CERNE organizes what the reform requires from each client.

Reform per client. Each client under the regular regime gets a compliance checklist: registry, tax regime and IBS and CBS fields. What is missing shows up on the client's card.
Requests via WhatsApp. What the client still owes becomes a request on WhatsApp, under the firm's rule, and repeats only for those who haven't responded.
Rejected invoice on the card. The rejection the client sends goes onto their card, with an owner and deadline, and doesn't get lost in the chat.
History for the price adjustment. The card keeps each client's requests for the month. In the fee conversation, the firm shows what was done.
Direct questions. In the AI assistant, the partner asks "which Presumido clients haven't reviewed their registry yet?". The answer comes with the firm's data.

The BPO and accounting package starts with an assessment of your firm. It uses modules already running at CERNE clients: the board with owner and deadline, and approval before anything is sent. See the workflows on the BPO and accounting page and the cards for each role. For the monthly routine, see how to collect documents from clients without repeating the request.

Start with an assessment

The hours in this article are examples. Your firm's come from your portfolio. Start with an assessment of your operation: our team builds the reform checklist per client and measures the work that goes into the fees. Book the assessment.

Frequently asked questions

What changes in the tax reform in 2027?: In 2027, PIS and Cofins are abolished, and CBS starts being collected. IPI goes to zero, except for products from the Manaus Free Trade Zone, and the Selective Tax begins, according to the Receita Federal page updated on October 16, 2026.
Is an invoice without IBS and CBS rejected?: For companies under the regular regime, yes. According to the IBS Management Committee, since August 3, 2026 an electronic tax document without the IBS and CBS fields is no longer authorized. Simples Nacional companies start showing both taxes only from 2027.
Does a company pay IBS and CBS in 2026?: The invoice shows 0.9% CBS and 0.1% IBS. According to Receita Federal, those who meet the ancillary obligations are exempt from paying that amount in 2026, which is a test year.
What is the deadline for Simples Nacional companies to opt for IBS and CBS outside the DAS?: Resolução CGSN 194/2026 extended the option for the regular IBS and CBS regime for 2027 to October 30, 2026. The option can be withdrawn from November 3 to December 20, 2026, according to CRC-SP.
Can an accounting firm charge more because of the tax reform?: It can, if the contract provides for it. Resolução CFC 1.590/2020 requires a written contract with the fee for each service, the adjustment rules and provision for amendments. Work not covered by the contract becomes a separate service.
Does accounting get a reduced IBS and CBS rate?: Yes. Art. 127 of LC 214/2025 cuts the IBS and CBS rates on accountants' services by 30%. For a legal entity, the reduction has requirements, such as all partners being licensed and the service being provided by them.

CERNE for BPO and accounting. Client portfolio, obligations with an owner, documents via WhatsApp, reconciliation and invoices in one system, alongside your accounting system. AI works inside the operation, and a team supports your management. See how it works or start with an assessment of your operation.

Sources

Victor Ferreira · Partner at IF Soluções and responsible for CERNE's architecture: the modules many companies share, the API integrations with the systems clients already use, data and security. Makes sure a workflow built for one client becomes a module that serves other markets.