Calculating Monthly Income Tax Withholding

Welcome back. In our previous lesson, we successfully navigated the deductions needed to calculate the Salaire Net Imposable (SNI), which is the base amount for calculating income tax. For our case study employee, Karim, we determined his SNI to be 8,620.50 DH.

Today, we will complete the tax calculation part of the payslip. Our objective is to apply the progressive Personal Income Tax (IR) scale to employment income to calculate the monthly tax withholding. This involves finding the correct tax rate for a given salary, applying a specific formula, and accounting for any family-related deductions. By the end of this lesson, you will have calculated the exact amount of income tax to be withheld from an employee's salary.

The Principle of Progressive Taxation

Before we jump into the numbers, it's important to understand the concept of a progressive tax system. In such a system, the tax rate increases as the taxable income increases. This means individuals with higher incomes pay a larger percentage of their income in taxes compared to those with lower incomes. Morocco uses this system for its Personal Income Tax (Impôt sur le Revenu - IR).

The tax is not calculated by simply multiplying your salary by a single rate. Instead, the income is divided into brackets (tranches), and a specific formula is applied depending on which bracket your income falls into.

1. Understanding the Moroccan IR Scale (Barème de l'IR)

The foundation of the IR calculation is the official tax scale provided by the Moroccan General Tax Code (Code Général des Impôts). This scale specifies the tax rates and deduction amounts for different monthly income brackets.

Let's examine the scale. The image below is your primary tool for this lesson.

As you can see, the table has three key columns for our calculation:

• Tranche de revenu (Salary Bracket): Defines the lower and upper limits for the monthly Salaire Net Imposable (SNI).
• Taux (Rate): The percentage rate applicable to the income within that bracket.
• Somme à déduire (Amount to Deduct): A fixed amount that is subtracted to adjust the calculation for the progressive nature of the tax. This simplifies the calculation so you don't have to calculate the tax for each bracket separately.

2. Calculating the Gross Tax (IR Brut)

The first step is to calculate the "gross" tax amount before any personal deductions. The formula for this is straightforward:

$\text{IR Brut}=(\text{Salaire Net Imposable}\times \text{Taux})-\text{Somme aˋ deˊduire}$

Let's apply this formula to our employee, Karim, whose SNI is 8,620.50 DH.

Step 1: Find the correct income bracket.
Karim's SNI of 8,620.50 DH falls between 6,666.67 DH and 15,000.00 DH.

Step 2: Identify the corresponding Rate and Amount to Deduct.
For this bracket, the table shows:

• Taux = 30%
• Somme à déduire = 1,433.33 DH

Step 3: Apply the formula.

• IR Brut = (8,620.50 DH × 30%) - 1,433.33 DH
• IR Brut = 2,586.15 DH - 1,433.33 DH
• IR Brut = 1,152.82 DH

So, Karim's gross monthly income tax is 1,152.82 DH. We are almost there, but there is one final adjustment to consider.

3. Applying Deductions for Dependents (Charges de Famille)

Moroccan tax law allows for a small deduction from the calculated IR Brut for dependents, referred to as charges de famille.

• Who qualifies? This includes the employee's spouse and dependent children, as per the conditions set by the Code Général des Impôts.
• Deduction Amount: The deduction is 30 DH per dependent per month.
• Ceiling (Plafond): The deduction is limited to a maximum of 6 people (e.g., a spouse and 5 children), for a total maximum deduction of 30 DH × 6 = 180 DH per month.

4. Calculating the Final Net Tax (IR Net)

The IR Net is the final amount of tax that will actually be withheld and paid to the state. The formula is:

$\text{IR Net}=\text{IR Brut}-\text{Deˊductions pour charges de famille}$

If an employee has no dependents, their IR Net is simply equal to their IR Brut.

Let's complete our example for Karim. Assume he is married and has two dependent children.

• Number of dependents: 1 (spouse) + 2 (children) = 3 dependents.
• Total family deduction: 3 × 30 DH = 90 DH.

Now, we calculate his IR Net:

• IR Net = IR Brut - Family Deductions
• IR Net = 1,152.82 DH - 90 DH
• IR Net = 1,062.82 DH

This, 1,062.82 DH, is the final income tax amount that will be deducted from Karim's monthly salary.

Test your understanding!

In the previous lesson's exercise, you calculated the Salaire Net Imposable (SNI) for an employee named Fatima, which was 12,881.00 DH.

Assuming Fatima is married with no children (1 dependent), calculate her IR Net. Use the tax scale provided in the lesson.

Show answer

1. Find the Bracket and Rates for an SNI of 12,881.00 DH:

   • The SNI falls into the bracket "6,666.67 to 15,000.00".
   • Taux = 30%
   • Somme à déduire = 1,433.33 DH

2. Calculate IR Brut:

   • IR Brut = (12,881.00 × 30%) - 1,433.33
   • IR Brut = 3,864.30 - 1,433.33
   • IR Brut = 2,430.97 DH

3. Calculate IR Net:

   • Fatima has 1 dependent (her spouse).
   • Family Deduction = 1 × 30 DH = 30 DH.
   • IR Net = IR Brut - Family Deduction
   • IR Net = 2,430.97 - 30
   • IR Net = 2,400.97 DH

Professional Insight: Staying Up-to-Date

A key responsibility for any accounting professional is to be aware that tax laws change. The IR scale, in particular, is often adjusted by the annual Finance Law (Loi de Finances). Using an outdated scale is a common and serious error.

For example, the image below shows a comparison between the current scale we have been using and a proposed new scale for the 2025 Finance Law.

While you should use the legally effective scale for your work, seeing this comparison reinforces the need for continuous professional monitoring. Always ensure you are working with the rates applicable to the period you are calculating for.

Conclusion

In this lesson, you have mastered a critical procedure in payroll accounting: calculating the monthly income tax withholding. You are now able to move from a calculated Net Taxable Salary to the final tax amount due.

Key Takeaways:

• The IR calculation is based on a progressive scale with different brackets and rates.
• The IR Brut is calculated with the formula: (SNI × Rate) - Amount to Deduct.
• The IR Net is the final tax amount after subtracting deductions for dependents (30 DH per dependent, capped at 6).
• Always verify you are using the current, legally effective tax scale, as it can change with new Finance Laws.

Preview of the Next Lesson:
We have now calculated all the major deductions from the gross salary: social contributions (CNSS, AMO) and income tax (IR). In our next lesson, we will put everything together to calculate the final Net Salary Payable (Salaire Net à Payer)—the actual amount the employee takes home.