Do companies in Nigeria pay 30% Company Income Tax on money market mutual fund investments through a corporate brokerage account?

You’re right to pause on this—corporate investing in money market funds in Nigeria is treated differently from individual investing, and tax can materially affect your net return.
Let’s separate facts from confusion.
1. What tax law actually applies
The law you’re referring to is the Companies Income Tax Act (CITA).
Standard Company Income Tax (CIT) rate:
30% for large companies
20% for medium companies
0% for small companies (turnover ≤ ₦25 million)
So yes—30% is real, but it doesn’t apply blindly to every investment income.
2. How money market mutual funds are taxed for companies
This is where many people get it wrong.
Income inside a money market fund typically comes from:
Treasury Bills
Commercial Papers
Bank deposits
Now the key:
(A) Interest from government securities
Income from:
Treasury Bills
FGN Bonds
➡️ Generally tax-exempt, even for companies.
(B) Interest from bank placements / commercial papers
This is the tricky part.
Interest earned may be subject to Withholding Tax (WHT) ~10%
BUT for companies:
WHT is usually not final tax
It’s treated as advance tax
So: ➡️ You may still be assessed under CIT depending on total profits.
3. Why people mention “30% tax”
That 30% applies when:
The income is considered part of your company’s taxable profit
After deducting allowable expenses
Then: ➡️ Your company pays CIT on net profit, not directly on the investment amount.
4. Important nuance (very critical)
If your company is:
Small company (≤ ₦25m turnover)
➡️ You likely pay 0% CIT ➡️ Only WHT may apply (and sometimes even refundable)
Medium/Large company
➡️ Investment income can:
Increase taxable profit
Lead to CIT liability (up to 30%)
5. Do you pay “extra tax” on the mutual fund itself?
No separate “mutual fund tax”
But you may have:
Withholding Tax deductions
CIT impact at company level
So the tax is: ➡️ Indirect, not at the fund level—but at your company level
6. Practical example
Let’s simplify:
Your company earns ₦1,000,000 from MMF
WHT deducted = ₦100,000
If you’re a large company:
That ₦1M goes into your total profit
You may pay CIT (30%) on overall profit
But:
That ₦100k WHT is credited against your tax
7. What most corporate investors overlook
Money market funds are not fully tax-free for companies
Structure matters:
Direct T-bills vs MMF
Company size
Total annual profit
8. Straight advice for your situation
Since you’re using a corporate brokerage account:
Confirm your company classification:
Small / Medium / Large
Ask the fund manager:
Breakdown of income sources (T-bills vs others)
Track:
WHT deductions
Annual tax computation
Bottom line
Yes, CITA (up to 30%) is real
But:
It applies to net company profits, not directly to the fund
Some MMF income (like T-bills) can be tax-exempt
Others may flow into taxable profit