Many companies plan around 30 June for Company Income Tax (CIT). It is a common date, not a universal one.
Your company’s CIT filing deadline normally depends on its accounting year-end. A new company must check two possible deadlines and file by whichever date comes first.
This guide explains how to find the deadline, prepare the required documents, decide which accounts to submit and review your figures before using Rev360.
Last reviewed on 27 July 2026. This guide is based on the Nigeria Tax Administration Act, 2025 and official transition guidance available on that date. Rev360 may change over time, so always follow the latest instructions shown in your company’s account.
Quick answer: when is a Company Income Tax return due?
Section 11(5) of the Nigeria Tax Administration Act, 2025 sets these filing times, subject to the Act, another tax law or a regulation:
| Your situation | Filing time in the Act | What to do |
|---|---|---|
| Company in business for more than 18 months | Not more than six months after the accounting year ends | Count six months from the company's own year-end. |
| Newly incorporated company | 18 months from incorporation or six months after the first accounting period ends, whichever is earlier | Calculate both dates; use the earlier one. |
| Company that permanently ceases trade or business in Nigeria | Not later than six months after cessation | Also address the cessation-year return and any outstanding return. |
Your situationCompany in business for more than 18 months
- Filing time in the Act
- Not more than six months after the accounting year ends
- What to do
- Count six months from the company's own year-end.
Your situationNewly incorporated company
- Filing time in the Act
- 18 months from incorporation or six months after the first accounting period ends, whichever is earlier
- What to do
- Calculate both dates; use the earlier one.
Your situationCompany that permanently ceases trade or business in Nigeria
- Filing time in the Act
- Not later than six months after cessation
- What to do
- Also address the cessation-year return and any outstanding return.
If your company’s financial year ends on 31 December, the filing deadline will usually be 30 June. If it ends on 31 March, the deadline will usually be 30 September. This is why 30 June is not the deadline for every company.
Section 11(1) also says every company must file an annual self-assessment return whether or not it owes tax. This includes a company granted exemption from incorporation, meaning one legally allowed to operate without being incorporated in Nigeria. A loss, a nil calculation or an expectation of small-company treatment is not, by itself, a reason to skip the return.
Use the TaxCalc.ng deadline calendar as a planning aid, then calculate from the actual dates in your records.
How does the first-return rule work for a new company?
“Whichever is earlier” means you do not choose the later, more convenient date. Compare the two statutory dates.
Example: a company is incorporated on 10 March 2026 and its first accounting period ends on 31 December 2026.
| Date to calculate | Result |
|---|---|
| 18 months from incorporation | 10 September 2027 |
| Six months after the first accounting period ends | 30 June 2027 |
| First return deadline | 30 June 2027 |
The example does not change the company’s accounting period or cover every unusual first-period situation. It shows the comparison required by section 11(5)(b). If the dates or period in your records are unusual, have the calculation checked before relying on it.
Which rules apply to a return around the 2026 transition?
The filing date is not the only date that matters. The Federal Government's transition guidance says tax returns relating to accounting periods ending before 1 January 2026 are filed under the previous tax laws, while returns relating to accounting periods ending on or after 1 January 2026 are administered under the new framework.
Start by writing down the dates on which the company’s accounting period begins and ends. For example:
| Accounting period ends | Practical starting point |
|---|---|
| 31 December 2025 | Review the previous tax laws and the transition guidance for that period. |
| 31 March 2026 | Start with the 2026 framework, then check facts specific to the company. |
| 31 December 2026 | Start with the 2026 framework. |
This transition check does not replace a tax computation for the company’s specific accounting period. See the calculation assumptions TaxCalc.ng uses.
What documents do you need for CIT filing?
For a resident company, section 11(1) lists the main items required for the annual self-assessment return. Get them ready before opening the portal:
- The required self-assessment form. This is the form prescribed by the tax authority. Complete it from figures you have already reviewed, not from estimates worked out while filing.
- Financial statements, tax computation and capital-allowances computation. As a general rule, the Act requires audited financial statements. It also requires tax and capital-allowances calculations for profit from each source.
- Evidence of payment of tax due. Check the amount due against payments already made. Include payment evidence where tax is due.
- Effective-tax-rate and additional-tax calculation, where applicable. This calculation checks whether the company’s effective tax rate triggers any additional tax under the Act. Prepare it only if it applies to the company.
- Principal-officer attestation. The appropriate senior company officer responsible for the return must review it and formally confirm that its information is correct.
There are special rules for a non-resident company, meaning a company that is not resident in Nigeria for tax purposes. Do not treat the short list above as its complete filing package. Section 11(2) requires additional financial statements, information about Nigerian operations and supporting schedules. Section 11(3) provides a limited exception for a non-resident company that earns only income subject to final withholding tax, where the tax withheld is the final Nigerian tax on that income.
Do small companies need audited financial statements for CIT filing?
Section 11(1)(b) makes a specific allowance: a small company's return may contain a statement of accounts formally confirmed by the taxpayer instead of audited financial statements. This is what the Act refers to as an attested statement of accounts.
The wording matters. It is an allowance for a company that qualifies as a small company under the applicable law; it is not a blanket rule that every small-looking business can use unaudited accounts. Confirm the company's status, prepare a proper attested statement where the allowance applies, and follow the current NRS filing instructions shown in the company’s account.
Prepare the figures before you use Rev360
Rev360 is the Nigeria Revenue Service taxpayer self-service platform. It is not the place to first discover whether the accounts agree with the tax computation.
Have these ready before you sign in:
- accounting-period start and end dates;
- company legal name, RC number and Tax ID;
- reviewed financial statements or, where the small-company allowance applies, a statement of accounts formally confirmed by the taxpayer;
- turnover and accounting profit or loss;
- tax adjustments, capital-allowance schedule, and available losses or reliefs where relevant;
- assessable profit and total profit as separately reviewed figures;
- tax credits, withholding-tax credits, prior payments and payment evidence, where relevant;
- the information needed for any effective-tax-rate or additional-tax calculation that applies; and
- the principal officer who will review and attest to the return, plus any properly designated representative who will handle it.
The Tax ID should be checked against the company record. Section 8 of the Act requires a Tax ID on returns and documents used for tax compliance. For the identity and registration context, read Tax Identification Number in Nigeria: what it is and where to start.
Keep these profit figures separate
The figures below do different jobs. Do not substitute one for another just because the numbers are close.
| Figure | Plain-English meaning | Why it matters here |
|---|---|---|
| Accounting profit before tax | The accounting result in the financial statements before tax | It is part of the financial-record starting point. |
| Assessable profit | A tax-computation figure | TaxCalc.ng uses it separately in supported Development Levy calculations. |
| Total profit | A tax-computation figure after the relevant statutory steps | TaxCalc.ng uses it separately in supported CIT calculations. |
FigureAccounting profit before tax
- Plain-English meaning
- The accounting result in the financial statements before tax
- Why it matters here
- It is part of the financial-record starting point.
FigureAssessable profit
- Plain-English meaning
- A tax-computation figure
- Why it matters here
- TaxCalc.ng uses it separately in supported Development Levy calculations.
FigureTotal profit
- Plain-English meaning
- A tax-computation figure after the relevant statutory steps
- Why it matters here
- TaxCalc.ng uses it separately in supported CIT calculations.
Use the Company Income Tax calculator guide to understand the supported inputs. It produces preparation figures, not a filed return or an audit.
A simple Rev360 filing process
Rev360 provides a Self Tax Filing section for company tax returns. The forms and documents you see may depend on your company type, filing period and the current version of the portal. Always follow the latest instructions shown in your account.
- Sign in to the official NRS taxpayer portal and confirm that you are viewing the correct company.
- Open Self Tax Filing and choose the Company Income Tax return or filing period shown for your company.
- Enter or upload the requested information using the figures and documents you already prepared.
- Check the calculation, warnings and declaration carefully against your financial statements and tax computation.
- Have the appropriate company officer review and attest to the return before submission.
- Complete any required payment step.
- Download and save the acknowledgement, submitted return, payment evidence and supporting documents.
Your company may not see exactly the same screens or document requests described above. Before filing a new return, also check whether there are older returns, unpaid assessments or missing payments that still need attention.
For broader portal preparation—including account access and record organisation—see Rev360 Nigeria: what businesses should prepare before filing. For cross-tax operational pitfalls, see common Rev360 filing mistakes businesses should avoid.
Can someone file for the company?
Yes, but the company still needs a clear responsible person. Section 11(6) requires every company to designate one or more representatives to attend to its tax matters. If the designated person is a paid agent, that person must be an accredited tax agent under the Act.
That representative role is separate from the section 11(1) requirement for a principal officer—the appropriate senior company officer—to review and attest to the return. Agree who will prepare, review and sign off before the deadline, especially where an external accountant prepares the computation.
Is a CIT return the same as a CAC annual return?
No. They are separate filings to different institutions.
| Filing | Administrator | What it is |
|---|---|---|
| Company Income Tax return | Nigeria Revenue Service | A tax self-assessment return. |
| CAC annual return | Corporate Affairs Commission | A corporate-registry compliance filing. |
FilingCompany Income Tax return
- Administrator
- Nigeria Revenue Service
- What it is
- A tax self-assessment return.
FilingCAC annual return
- Administrator
- Corporate Affairs Commission
- What it is
- A corporate-registry compliance filing.
Completing one does not automatically complete the other. The CAC's company guidance describes its annual-return process separately, including submission of a statement of accounts (or a letter explaining its absence) within the CAC process. Keep separate reminders and retain separate acknowledgements.
Company Income Tax filing checklist
- I identified the accounting period and checked which transition framework applies.
- I calculated the statutory deadline from the company facts, including both dates for a first return.
- I reviewed earlier CIT returns, acknowledgements, assessments, credits and payments.
- The company name, RC number and Tax ID agree across the records.
- The financial statements—or the permitted small-company statement of accounts—are ready.
- The tax and capital-allowances computations have been reviewed.
- Accounting profit, assessable profit and total profit have not been mixed up.
- I have payment evidence where tax is due and required.
- I checked whether an effective-tax-rate or additional-tax computation applies.
- The appropriate principal officer has reviewed and attested to the return.
- I will save the submitted return, acknowledgement and supporting file after submission.
What TaxCalc.ng can—and cannot—do for a CIT filing
TaxCalc.ng can help you understand the deadline rules, keep supported profit inputs separate, estimate CIT and Development Levy for supported cases, and prepare figures for review before filing.
TaxCalc.ng does not submit a return to NRS, issue Rev360 credentials, create or retrieve a Tax ID, prepare audited financial statements, or replace an accountant, auditor or tax adviser. Non-resident, free-zone, insurance, petroleum, hydrocarbon and certain multinational cases need specialist review.
Frequently asked questions
Is the CIT filing deadline always 30 June in Nigeria?
No. It is commonly 30 June where the accounting year ends on 31 December. Section 11(5) instead uses six months after the accounting year-end for a company that has been in business for more than 18 months.
What is the first Company Income Tax filing deadline for a new company?
Calculate 18 months from incorporation and six months after the first accounting period ends. The first-return deadline is the earlier of those two dates.
Does a company file a return if no tax is payable?
Section 11(1) requires the annual self-assessment return whether or not the company is liable to pay tax. The return and payment questions are therefore not identical.
Can a small company file unaudited accounts for CIT?
The Act allows a qualifying small company's return to contain a taxpayer-attested statement of accounts in place of audited financial statements. Confirm qualification and the current NRS filing instructions before relying on that route.
Where do I file Company Income Tax in Nigeria?
NRS currently provides Self Tax Filing through its Rev360 taxpayer self-service platform. Use the official portal and the current instructions for the company's account.
Sources reviewed
- Nigeria Tax Administration Act, 2025—National Assembly official copy, especially sections 8 and 11.
- Federal Ministry of Finance transition guidance for the Tax Acts 2025.
- Nigeria Revenue Service taxpayer self-service portal.
- Corporate Affairs Commission company guidance.
Disclaimer
TaxCalc.ng provides estimates and compliance-preparation information for planning and documentation. It is independent of NRS, CAC and other government agencies. Tax law, a company's facts and portal instructions can change; review the applicable requirements and obtain qualified advice before filing or paying tax.
