Nigeria Tax Administration Act, 2025 · Circular 2026/21 ¶9.1
The gain is worked out in dollars first
Naira falling in value is not a profit. The gain is measured in dollars, then converted once.
Who this lands on: Anyone disposing of a Category 1, 3, 4 or 5 asset.
This is the part most people get wrong, and it is in your favour. The gain on a virtual asset is worked out in US dollars — dollar proceeds less dollar cost base — and only that dollar gain is converted to naira, at the CBN/NAFEM rate on the disposal date.
Step 1: dollar cost base. For a naira purchase, the total naira paid divided by the tokens you actually received after stamp duty, converted at the rate on the acquisition date. For a swap, the dollar market value of what you received on the swap date.
Step 2: dollar proceeds. For a sale for naira, the naira received divided by the rate on the disposal date. For a swap, the dollar market value of what you received.
Step 3: dollar gain or loss — proceeds less cost base.
Step 4: multiply the dollar gain by the rate on the disposal date. That naira figure is the assessable gain.
Step 5: withholding, where it applies, is taken in tokens from the gross proceeds — not from the gain.
The circular's own worked example: 0.985 BTC bought for ₦1,000,000 at ₦1,000 to the dollar is a cost base of $1,000. Sold later for ₦1,970,000 at ₦1,500 to the dollar, the proceeds are $1,313.33 and the dollar gain is $313.33. The taxable naira gain is ₦470,000 — not the ₦970,000 a straight naira-to-naira sum would show. The ₦500,000 difference is naira depreciation, and it is expressly not income.
Where a token is not priced in dollars, convert through its main trading pair at the moment of the transaction, using a price source the Service has approved. If no verifiable price exists anywhere, write down how you valued it and keep that note for six years.