Effective tax rate (ETR) is commonly used to measure the tax burden of a company relative to its profits. While companies have historically considered ETR as a financial reporting and tax planning metric, the Nigeria Tax Act (NTA) 2025 gives the concept greater significance by introducing a statutory minimum ETR for specified companies.
Effective from 1 January 2026, the NTA 2025 requires companies within the scope of the minimum ETR provisions to maintain an effective tax rate of at least 15%. Where the applicable ETR is below 15%, the company is required to pay additional tax to bring its ETR up to the prescribed minimum.
The provision introduces an important consideration for large companies and multinational groups. Tax planning can no longer focus solely on reducing taxable profits or the company's ordinary tax liability. Companies must also consider how their tax positions affect their overall effective tax rate.
Here is what companies need to know.
1. The 15% ETR Is a Minimum Tax Floor
The introduction of the 15% minimum ETR should not be interpreted as a reduction of the standard corporate income tax rate to 15%.
In practical terms, a company first determines its tax liability under the ordinary provisions of the NTA. It then considers whether its effective tax rate, determined in accordance with Section 57, is at least 15%. Where the resulting ETR is below 15%, an additional tax may arise. This creates two distinct stages in determining the company's tax position:
The second stage is particularly important for companies whose tax liability is significantly reduced by incentives, credits, deductions or other tax reliefs.
2. Who Is Subject to the Minimum ETR?
The minimum ETR does not apply to every company operating in Nigeria.
Under Section 57 of the NTA 2025, the provision applies to:
Accordingly, a large Nigerian company may fall within the minimum ETR regime even where it has no multinational parent or group relationship.
Companies should therefore assess both their turnover and group structure when determining whether Section 57 applies to them.
3. How Is the ETR Determined?
The statutory ETR calculation is not simply the tax expense reported in the financial statements divided by accounting profit. Section 57 provides specific rules for determining both the tax and profit components of the calculation.
For the purpose of determining the relevant profit, the NTA starts with the company's net profit before tax as reported in its audited financial statements excluding Franked Investment Income and unrealistic gain or loss.
The effective tax rate can therefore be expressed conceptually as:
Effective Tax Rate = Aggregate Covered Tax Paid ÷ Relevant Profit × 100
The calculation must, however, be performed in accordance with the definitions and adjustments prescribed by the NTA.
This distinction is important because the ETR disclosed in a company's financial statements may not necessarily be the same as the ETR calculated for tax purposes under Section 57.
4. What Is Aggregate Covered Tax?
The tax component of the calculation is equally important.
The NTA 2025 defines aggregate covered tax paid by reference to income taxes paid by the company under the Act.
Companies should therefore identify the taxes that fall within the statutory definition before calculating their ETR.
The use of the term "covered tax" means that companies should not simply take the total amount of taxes, levies and statutory payments made during the year and assume that all of them form part of the ETR calculation. A properly documented covered-tax schedule should be prepared to demonstrate how the amount used in the calculation was determined.
5. Why Might a Company's ETR Fall Below 15%?
A company can have a significant accounting profit while recording an effective tax rate below the statutory minimum. This can occur where the company benefits from tax incentives, credits or other provisions that reduce the amount of tax payable relative to its relevant profit.
For example, a company may have substantial deductions or tax reliefs that significantly reduce its ordinary tax liability. Although these claims may be valid under the NTA, their cumulative effect could result in an ETR below 15%.
For companies subject to Section 57, this creates further tax consideration.
The question is therefore no longer simply whether a tax position is allowable. Companies should also consider the effect of that position on their minimum ETR exposure.
What is the net tax benefit after considering the minimum ETR?
This is particularly important when evaluating investment decisions or incentives that produce substantial reductions in the company's tax liability.
Tax planning should therefore consider the interaction between the incentive and the minimum ETR rather than assessing each provision independently.
6. Capital Allowances Should Also Be Considered
Capital allowances remain an important mechanism for providing tax relief on qualifying capital expenditure.
However, for companies within the minimum ETR regime, the tax benefit from capital allowances should be considered alongside the company's overall ETR.
A significant capital allowance claim can reduce taxable profits and, consequently, the company's ordinary tax liability. Where the resulting tax covered produces an ETR below 15%, the company may have an additional tax exposure.
This does not mean that companies should refrain from claiming legitimate capital allowances. Rather, it reinforces the need to evaluate the overall tax consequence of significant tax deductions and allowances.
7. ETR and Tax Planning: A Change in Perspective
The introduction of the minimum ETR changes an important aspect of corporate tax planning.
Tax planning has traditionally focused on questions such as:
For companies within Section 57, another question must now be added:
What will the company's effective tax rate be after applying these tax positions?
This does not reduce the importance of legitimate tax planning. Instead, it makes the analysis more comprehensive.
A transaction or tax position should be evaluated based on its overall tax impact, rather than simply the reduction in ordinary tax liability that it creates.
8. Financial Reporting and Tax Compliance Are Now More Closely Connected
The ETR calculation under the NTA begins with information from the company's audited financial statements.
Consequently, finance and tax teams need to work closely together in preparing the ETR assessment.
Finance teams should identify the relevant accounting figures, while tax teams should determine the statutory adjustments and covered taxes required for the calculation.
This is particularly relevant for companies with:
An ETR review should therefore form part of the year-end tax process rather than being performed only after the tax computation has been completed.
9. Documentation Will Be Critical
Companies subject to the minimum ETR should maintain clear working papers supporting their calculation.
The documentation should provide a clear trail from the audited financial statements to the final ETR and, where applicable, the additional tax payable.
Companies should consider maintaining:
A well-supported ETR computation will also make it easier to respond to questions during a tax audit or review by the Nigeria Revenue Service.
What Companies Should Be Doing Now
1. Determine whether Section 57 applies.
Review the company's turnover and group structure.
2. Incorporate ETR into the year-end tax process.
Do not wait until the annual tax return is ready before performing the assessment.
3. Prepare a separate statutory ETR computation.
The financial statement ETR should not automatically be used as a substitute.
4. Review the company's covered taxes.
Ensure that only amounts falling within the statutory definition are included.
5. Assess the impact of tax incentives and credits.
Consider their effect on both the ordinary tax liability and the ETR.
6. Review significant deductions and capital allowances.
Assess whether major tax reliefs could create an ETR exposure.
7. Quantify additional tax early.
Where the ETR is below 15%, determine the resulting additional tax liability before filing.
8. Maintain adequate supporting documentation.
Ensure that the calculation can be reconciled to the financial statements and supporting tax records.
The Bottom Line
The minimum effective tax rate introduced by the Nigeria Tax Act 2025 adds a new layer to corporate tax planning and compliance for companies within its scope.
The objective of tax planning can no longer be viewed solely as reducing the company's ordinary tax liability. Companies must also consider whether their resulting tax position satisfies the statutory minimum ETR.
The key question for affected companies is therefore no longer simply:
"How much tax can we legitimately save?"
It is:
"What is the overall tax outcome after considering the minimum ETR?"
For finance and tax teams, this means incorporating ETR analysis into tax planning, year-end reporting and annual tax compliance. Doing so will help companies identify potential additional tax exposures early, properly evaluate the benefit of tax incentives and deductions, and maintain a defensible tax position under the NTA 2025.