CPB: the 150,000 euro threshold also applies when switching from flat-rate to simplified tax regime

Context

TL;DR

• Italian CPB flat-rate taxpayers bound for 2 years, even if switching to simplified regime.
• €150,000 revenue threshold for CPB exit, 50% above standard flat-rate exit threshold.
• Cross-border workers in Ticino can manage revenue fluctuations within €150,000 limit.
• CPB remains valid up to €150,000, but exceeds threshold terminates agreement.

Key facts

• Ruling Number: 87
• Publication Date: March 30, 2026
• Flat-rate Exit Threshold: €100,000
• CPB Exit Threshold: €150,000
• Legislative Decree: No. 13/2024
• Cross-border Workers: Ticino residents working in Lombardy
• Tax Regime Change: Switching from flat-rate to simplified regime does not invalidate CPB
• Revenue Monitoring: Taxpayers must monitor revenue to stay below €150,000 threshold

On March 30, 2026, the Italian Revenue Agency published ruling no. 87, which clarifies a crucial point for Italian taxpayers who joined the Biennial Preventive Agreement (CPB) as flat-rate taxpayers and then transitioned to the simplified regime. The principle is straightforward: anyone who joined the CPB under the flat-rate regime remains bound by the rules of that regime for the entire two-year period, regardless of any changes in accounting practices.

The case analyzed by the Agency concerns a taxpayer who, in 2023, operated under the flat-rate regime. By October 31, 2024, they had joined the CPB by completing the LM section of the Income Tax Return (Modello Redditi) in the dedicated flat-rate section. During 2024, the same taxpayer voluntarily switched to the simplified regime, despite remaining below the €100,000 revenue threshold that would have automatically excluded them from the flat-rate regime. The Agency clarified that this transition does not constitute grounds for exclusion or automatic termination of the CPB but does not alter the initial subjective qualification: the taxpayer remains bound by the limits applicable to those who joined as flat-rate taxpayers.

The key point is the €150,000 revenue or compensation threshold, which represents the tolerance band introduced by the legislator with Legislative Decree No. 13/2024. For those who joined the CPB as flat-rate taxpayers, the exit threshold from the agreement is equal to the standard flat-rate regime exit threshold (€100,000) increased by 50%. This means that, up to €150,000 in revenue, the CPB remains valid, but once this threshold is exceeded, the agreement ceases to apply from the tax period in which the limit is surpassed.

The Revenue Agency’s ruling introduces an important element of clarity for taxpayers operating in Lombardy but residing in Ticino, where the issue of cross-border tax regimes between Italy and Switzerland is always delicate. For these cross-border workers, the rule represents a stability opportunity: the €150,000 threshold allows them to manage physiological fluctuations in revenue without losing the benefits of the agreement, provided they remain within the expanded limit.

How the CPB threshold works for flat-rate taxpayers

As referenced in the ruling, the legislation governing the termination causes of the CPB is outlined in Article 32, paragraph 1, letter b-bis of Legislative Decree No. 13/2024. The mechanics are structured on two levels:

• Between €100,000 and €150,000: the taxpayer exits the flat-rate regime but not the CPB. The agreement remains valid for the current tax period, allowing them to continue benefiting from the applicable concessions.
• Above €150,000: the CPB ceases to apply from the same tax period in which the threshold is exceeded. Income is then determined according to the rules of the regime actually adopted (in this case, the simplified regime), with the application of ordinary taxation. Any advance payments made under the CPB must be recalculated accordingly.

This mechanism was introduced to ensure stability in concordatary choices, preventing physiological revenue fluctuations from jeopardizing an agreement already formalized. For Ticino cross-border workers, who often operate within two tax systems, the rule represents an element of predictability.

📊 Why the Italian Revenue Agency provided this clarification

Ruling no. 87 was issued to resolve a practical doubt: what happens if a taxpayer, after joining the CPB as a flat-rate taxpayer, decides to change their tax regime during the two-year period? The Agency emphasized that the subjective qualification under which the CPB was joined is decisive. Switching from the flat-rate to the simplified regime does not alter the nature of the agreement already entered into, nor does it invalidate it. However, all the rules applicable to flat-rate taxpayers remain in force, including the €150,000 threshold.

This principle prevents disparities between taxpayers who maintained the flat-rate regime throughout the period and those who, despite transitioning to the simplified regime, remain bound by the original rules. A distinction that, for cross-border workers, can make all the difference in terms of tax planning and revenue management.

Operational details

For Ticino cross-border workers employed in Lombardy, the clarification provided by Italy’s Revenue Agency introduces an element of fiscal predictability worth careful analysis. The shift from the flat-rate regime to the simplified one is a choice many taxpayers consider due to greater accounting flexibility or business growth needs. However, once the CPB (Concordato Preventivo Biennale) has been adopted under the flat-rate system, the €150,000 revenue threshold becomes a critical parameter—even after changing regimes.

Concrete scenarios for cross-border workers

Let’s consider the case of a self-employed professional residing in Ticino but primarily operating in Lombardy. In 2023, they worked under the flat-rate regime with annual revenues of €90,000. By October 2024, they join the CPB as a flat-rate taxpayer, benefiting from greater fiscal stability. During 2024, their business grows, and revenues reach €120,000. Despite exceeding €100,000, they remain below the €150,000 threshold. In this case, the CPB remains valid: the taxpayer continues to enjoy the benefits of the agreement, even after exiting the flat-rate regime.

If, however, 2024 revenues reach €160,000, the CPB ceases to apply from the same tax period. Income must then be calculated under the simplified regime rules, with ordinary taxation applied. Any advance payments made under the agreement must be recalculated, and the taxpayer loses the benefits of the agreement for that year. This scenario is particularly relevant for cross-border workers who, due to double taxation or divergent fiscal rules between Italy and Switzerland, must plan their revenues with great care.

📊 Key takeaway: The €150,000 threshold applies regardless of the chosen fiscal regime.

Comparing before and after the Revenue Agency’s clarification

Before the ruling on interpellation no. 87, many taxpayers wondered whether switching from the flat-rate to the simplified regime could free them from CPB constraints. The Agency has now clarified that this is not the case: the initial subjective qualification is decisive. This means that for Ticino cross-border workers, fiscal planning must account not only for Italian rules but also Swiss regulations—especially when managing revenues in a cross-border context.

Before the clarification:

• It was assumed that switching to the simplified regime could automatically exclude the taxpayer from the CPB.
• There was no clarity on the reference threshold for the termination of the agreement.

After the clarification:

• The CPB remains valid up to €150,000 in revenues, regardless of the adopted fiscal regime.
• The taxpayer remains bound by the rules applicable to flat-rate taxpayers, even after changing regimes.

⚠️ Critical insight: The initial regime choice (flat-rate vs. simplified) does not override the CPB’s applicability.

What Ticino cross-border workers should do

For those operating in Lombardy, this clarification necessitates a review of fiscal strategies. In particular, it is essential to:

• Constantly monitor revenues: exceeding €150,000 results in the loss of CPB benefits for the current tax year.
• Assess the choice of fiscal regime: if revenues are expected to grow beyond €100,000, it may be worth evaluating whether to maintain the flat-rate regime or opt for the simplified one from the start of the biennial period.
• Plan ahead: to avoid surprises, it is advisable to periodically calculate revenues and adjust the fiscal strategy accordingly.

💡 Pro tip: Cross-border workers should integrate Italian and Swiss fiscal rules into their long-term planning to optimize benefits and compliance.

Impact on cross-border workers residing in Ticino

For Ticino’s cross-border workers, the issue of overlapping tax regimes between Italy and Switzerland has always been complex. The clarification issued by the Italian Revenue Agency introduces an element of stability, but also responsibility: the €150,000 threshold becomes a key parameter that must be carefully observed, especially when operating under two different tax systems.

In Ticino, where taxation is generally more favorable compared to Lombardy, many cross-border workers consider optimizing their income to minimize tax impact. However, the CPB threshold imposes a strict limit that must be respected to avoid losing the benefits of the agreement. This means that for high-earning cross-border workers, the choice between the flat-rate and simplified regimes must be made with extreme care, taking into account not only Italian rules but also Swiss regulations.

📊 Comparative tables: flat-rate vs. simplified regime under the CPB

This table highlights how, despite the transition to the simplified regime, the CPB constraints remain unchanged for those who initially opted for the flat-rate system. The choice of tax regime, therefore, must be evaluated not only based on accounting needs but also in light of the €150,000 threshold and the benefits of the CPB agreement.

Useful tools to protect your net income

To reduce FX leakage, compare CHF-EUR exchange options and banks for cross-border workers.

Key points

For Ticino cross-border workers who work in Lombardy and have joined the CPB as flat-rate workers, the transition to the simplified regime does not change the constraints of the threshold of 150 thousand euros. This means that it is essential to constantly monitor your revenues and carefully plan your tax strategies. Here is a practical guide to better manage this situation.

Step 1: Check your CPB status and revenue threshold

The first step is to check if you are already a member of the CPB and in what capacity. If you joined as a lump sum in 2024, the threshold of 150 thousand euros is binding for the entire two-year period 2024-2025. To do this verification, you can:

• Consult the 2024 tax return (PF Income Model), in particular the LM form where membership of the CPB is indicated. - Check the revenues or fees for 2024: if they exceed 100 thousand euros but less than 150 thousand euros, the CPB remains valid even if you have exited the flat-rate regime. - If revenues exceed 150 thousand euros, the CPB ceases to produce effects for 2024, and the income must be calculated according to the rules of the simplified regime.

Step 2: Calculate revenue in real-time

To avoid exceeding the threshold of 150 thousand euros without realizing it, it is advisable to monitor revenues on a monthly or quarterly basis. This allows you to adapt your tax strategy in advance. For example:

• If you expect to exceed 150 thousand euros during the year, it is useful to consider whether to reduce revenues (for example, by postponing some invoices) or opt for a different tax planning. - If you remain below 100 thousand euros, there are no problems: the CPB remains valid and you can continue to benefit from the benefits. - If you are between 100 thousand and 150 thousand euros, the CPB is still valid, but it is necessary to prepare for the transition to the simplified regime for 2025.

Step 3: Evaluate the choice of tax regime for 2025

If you have transitioned to the simplified regime in 2024, but revenue growth is expected, it is useful to evaluate whether to maintain the simplified regime for 2025 or whether to return to the flat-rate regime. However, if the threshold of 100 thousand euros has already been exceeded, the flat-rate regime is no longer an option for 2025. In this case, the choice comes down to:

• Simplified regime: more flexible, but with more articulated accounting obligations. - Ordinary regime: for activities with very high revenues or complex costs to manage.

Step 4: Adapt your tax planning

If the threshold of 150 thousand euros is exceeded, the CPB ceases to produce effects for 2024. This involves:

• The income must be calculated according to the rules of the simplified regime (or ordinary, if applicable). - Advances paid on the basis of the CPB will have to be recalculated and, if necessary, topped up or refunded. - For 2025, you will no longer be able to benefit from the CPB, unless you are within the limits set for a new membership.

Step 5: Consult an accountant specializing in cross-border commuters

Given the complexity of the Italian-Swiss tax rules, it is advisable to contact a professional who knows both Italian and Ticino legislation. A specialized accountant can help you:

• Evaluate the convenience of the flat-rate vs. simplified regime. - Plan revenues so as not to exceed the threshold of 150 thousand euros. - Manage tax compliance in Italy and Ticino, avoiding double taxation or errors.

Deadlines and obligations

• By 31 October 2025: deadline for joining the CPB for the two-year period 2025-2026. If you intend to continue to benefit from the arrangement, you must submit your application by this date. - By 30 November 2025: deadline for the payment of the second advance payment of taxes for 2025. If the threshold of 150 thousand euros has been exceeded in 2024, it is necessary to recalculate the advances according to the new tax regime.

Useful tools on the Frontaliere Ticino website

To help cross-border commuters better manage this situation, the Frontaliere Ticino website offers several practical tools:

• calcolatore-reddito-frontalieri: allows you to simulate the net income based on the tax regime and residence. - confronto-regimi-fiscali: compare the IRPEF rates, deductions and benefits of the flat-rate vs. simplified regime. - guida-cpb: explains how to join the CPB and what the benefits are. - calendario-scadenze: lists all the tax deadlines for cross-border commuters in Ticino and Lombardy.

What happens if the threshold of 150 thousand euros is exceeded?

Exceeding 150 thousand euros in revenues involves the loss of the benefits of the CPB for the current tax period. In this case:

• Income is calculated according to the rules of the simplified (or ordinary) regime. - Advances paid based on the CPB must be recalculated. If you have paid too much, you can ask for a refund; if too little has been paid, it will have to be integrated. - For 2025, you will no longer be able to benefit from the CPB, unless you are within the limits set for a new membership.

This scenario is particularly relevant for cross-border commuters who, due to double taxation or divergent tax rules, have to plan their revenues carefully. If you expect to exceed the threshold, it is helpful to consider alternative strategies, such as diversifying your assets or planning your investments.

Frequently Asked Questions

Can I switch from the flat-rate regime to the simplified regime without losing the CPB?

Yes, the transition from the flat-rate regime to the simplified regime does not automatically entail the termination of the CPB. However, all the rules provided for flat-rate taxpayers remain applicable, including the threshold of 150 thousand euros in revenues. For this reason, it is essential to constantly monitor your revenues so as not to exceed the limit.

What happens if I exceed 150 thousand euros in revenues?

If revenues exceed 150 thousand euros, the CPB ceases to produce effects from the same tax period in which the threshold is exceeded. The income will then be calculated according to the rules of the simplified (or ordinary) regime, and the advances paid on the basis of the CPB will have to be recalculated.

Do I have to recalculate the advances if I exceed the threshold?

Yes, if the threshold of 150 thousand euros is exceeded, it is necessary to recalculate the advance taxes according to the new tax regime. If you have paid too much, you can ask for a refund; If you have paid too little, you will have to supplement the payment.

Can I join the CPB for the two-year period 2025-2026 if I have exceeded the threshold in 2024?

No, if the threshold of 150 thousand euros has been exceeded in 2024, you can no longer benefit from the CPB for 2025. The threshold is binding for the entire tax period in which it is exceeded, and the CPB ceases to produce effects from that moment.

How can I track my revenue so that I don't exceed the threshold?

It's a good idea to track your revenue on a monthly or quarterly basis, such as using a simple Excel table or accounting software. This way, you can intervene early to adjust your tax strategy or postpone some invoices if necessary.

Source: varesenews.it