AI agents for business finance: what they can and can't do
What AI agents can do in bookkeeping, close, collections and compliance today, where a person must stay in charge, and how to judge a product.
The short answer
Report the gain in your home currency: convert the cost at the rate on the date you bought and the proceeds at the rate on the date you sold, then apply your country's capital gains rules. Because the naira has fallen, a naira profit on NGX shares can be a loss in pounds, dollars or Canadian dollars. In the UK the 2026-27 allowance is £3,000 with rates of 18% and 24%; in Canada half the gain is taxable; in the US gains go on Form 8949 and Schedule D.
Diaspora investors who bought Nigerian bank or industrial stocks through a stockbroker often only think about the Nigerian side when they sell. If you are resident abroad, your country of residence usually taxes the gain too, and it measures that gain in its own currency.
The Nigerian side first
Under the Nigeria Tax Act 2025, individuals' gains are added to income and taxed at personal income tax rates rather than the old flat 10% (Bloomberg Tax, February 2026). Disposals of shares are exempt where proceeds are no more than ₦150 million and gains no more than ₦10 million in a 12-month period (Bloomberg Tax; Mondaq, 2026, citing section 34). Mondaq also mentions relief where proceeds are reinvested, without giving the period. How these rules apply to a non-resident seller is covered in selling Nigerian shares as a non-resident.
Computing the gain in your home currency
Tax offices abroad want the figures in their own currency. The IRS says all amounts must be in US dollars at the rate prevailing when each item is received or paid; the CRA says to convert at the Bank of Canada rate for the day the amount arises (Folio S5-F4-C1). In practice:
- Convert the purchase cost, including broker commission and fees, at the rate on the purchase date.
- Convert the sale proceeds, less selling costs, at the rate on the sale date.
- The difference is your gain or loss for your return.
Worked example
Example only, with invented rates. You bought shares for ₦2,000,000 when ₦500 bought £1, and sold them for ₦3,000,000 when ₦2,000 bought £1.
| Naira | Sterling | |
|---|---|---|
| Cost | ₦2,000,000 | £4,000 |
| Proceeds | ₦3,000,000 | £1,500 |
| Result | ₦1,000,000 gain | £2,500 loss |
In naira you made 50%. In sterling you lost £2,500. Whether that loss can be used depends on your country's rules; for the treatment of currency losses generally, see lost money to naira devaluation.
United Kingdom
GOV.UK (updated October 2026) gives a 2026-27 annual exempt amount of £3,000, with gains taxed at 18% within the basic rate band (£37,700) and 24% above it. Gains are reported through Self Assessment, or the real-time Capital Gains Tax service for UK residents. GOV.UK notes that the real-time service cannot be used to claim foreign tax credit relief on overseas property; if you need credit for Nigerian tax on shares, check whether the same limit applies before choosing the real-time route. If you claim the new foreign income and gains regime as a recent arrival, LITRG notes you lose the annual exempt amount for that year.
United States
IRS Topic 409 (September 2026) treats shares as capital assets. Shares held more than one year give long-term gains; for 2025 the long-term rates were 0%, 15% and 20% depending on income. You report each sale on Form 8949, then Schedule D. Capital losses offset gains, with up to $3,000 a year ($1,500 if married filing separately) against other income and the rest carried forward. Nigerian tax on the gain, if any, may be claimed as a foreign tax credit.
Canada
The CRA's capital gains guide (T4037) uses a one-half inclusion rate: half the gain is taxable. Cost is the adjusted cost base in Canadian dollars; convert each purchase and sale at the Bank of Canada rate for its date. NGX shares may also count towards the T1135 foreign property threshold of C$100,000.
Ireland
PwC's Ireland summary (August 2026) gives capital gains tax of 33% with an annual exemption of €1,270. Irish-domiciled residents are taxed on worldwide gains; non-domiciled residents on foreign gains only when remitted.
Common mistakes
- Reporting the naira gain converted at one rate. Converting the naira profit at the sale-date rate ignores the currency movement since purchase and usually overstates the gain.
- Ignoring bonus shares. A bonus issue, such as one new share for every four held, spreads your original cost over more shares; it is not a free gain to report separately as income.
- Leaving out dividends. Dividends received while you held the shares are income in the year received, separate from the gain (see withholding tax on Nigerian dividends).
- Forgetting small sales. Each disposal is reported, even if the Nigerian exemption covered it at home.
- Losing the cost evidence. Without contract notes, proving your purchase price years later is hard; request copies from your broker before you sell.
Records to keep
- Contract notes for each purchase and sale from your stockbroker.
- CSCS statements showing holdings and transfers.
- Bonus and rights issue notices, which change your number of shares and cost per share.
- Bank statements showing the naira proceeds and any conversion.
Where Pryme fits
Sale proceeds paid in naira can sit in your Pryme NGN balance, alongside GBP, USD and EUR, until you decide to Swap; the dated conversion record helps when you compute the home-currency figure. See multicurrency.
Questions people ask
Do I pay UK tax on profit from selling Nigerian shares?
If you are UK resident, generally yes, on the gain measured in sterling, above the £3,000 annual exempt amount for 2026-27, at 18% or 24%.
My shares rose in naira but fell in dollars. What do I report in the US?
The IRS wants dollar figures, so you report the dollar result. A naira gain can be a dollar loss once both dates' rates are applied.
Are Nigerian share gains taxed in Nigeria under the new law?
Gains are added to income at personal income tax rates, but share disposals with proceeds up to ₦150 million and gains up to ₦10 million in 12 months are reported as exempt.
Which documents prove my cost for NGX shares?
Broker contract notes, CSCS statements and records of bonus or rights issues.
Sources
- Bloomberg Tax: New Nigeria tax law redefines capital gains tax for individuals · accessed Oct 2026
- Mondaq: Changes in chargeable gains under the Nigerian Taxation Act · accessed Oct 2026
- GOV.UK: Capital Gains Tax rates and allowances · accessed Oct 2026
- IRS Topic 409: Capital gains and losses · accessed Oct 2026
- CRA T4037: Capital gains · accessed Oct 2026
- PwC: Ireland, income determination · accessed Oct 2026
This article is general information, not financial, legal or tax advice. Products described are provided under the terms on this site and are subject to regulation and eligibility.